Network based multiple sensor and control device with temperature sensing and control

ABSTRACT

A multifunction sensor device which provides various transducer functions including means for performing temperature sensing, humidity sensing, ambient light sensing, motion detection, thermostat functions, switching functions, load switching and dimming functions, displaying actual and set temperature values, displaying time of day values and a means to put the device in an on, off or auto mode. The device has utility in environments such as that found in offices, schools, homes, industrial plants or any other type of automated facility in which sensors are utilized for energy monitoring and control, end user convenience or artificial or natural cooling, heating and HVAC control. The device can be used as a switch or dimmer, sensor or thermostat as well as to adjust and control all natural and artificial lighting, temperature and humidity devices. Key elements of the invention include overcoming the difficulty of mounting diverse sensors or transducers within the same device or housing; permitting these various sensors to exist in a single package that can be mounted to a wall in a substantially flush manner; and eliminating the requirement of an air flow channel in the device, thus minimizing any adverse effects on the motion detecting element or sensor as well as providing built in partial hysteresis. The device may include additional transducers or sensors and is constructed such that the temperature and humidity sensors are neither exposed to the flow of air in a room or area nor in an airflow channel whereby a chimney effect may occur. The device can transmit and receive real time data, relative data and actual discrete data in addition to switching and controlling loads locally or remotely. An embodiment utilizing airflow channels to direct air over the temperature and humidity sensors is also disclosed.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/085,814, filed May 18, 1998.

FIELD OF THE INVENTION

The present invention relates generally to the field of electricalsensors and more particularly to a network based multi-function sensorand control device suitable for sensing motion, temperature, humidityand ambient light, setting and controlling temperature and control relayand ballast loads and which includes blinder devices for reducingnuisance tripping of the device.

BACKGROUND OF THE INVENTION

Today, automation systems are being installed in more and morebuildings, including both new construction and in structures that arebeing rebuilt. The incentives for putting automation systems into abuilding are numerous. High on the list are reduced operating costs,more efficient use of energy, simplified control of building systems,ease of maintenance and of effecting changes to the systems. Facilitymanagers would prefer to install systems that can interoperate amongsteach other. Interoperability is defined by different products, devicesand systems for different tasks and developed by differentmanufacturers, being able to be linked together to form flexible,functional control networks.

An example of a typical automation system includes lighting controls,HVAC systems, security systems, fire alarm systems and motor drives allpossibly provided by different manufacturers. It is desirable if theseseparate disparate systems can communicate and operate with each other.

Prior art automation systems generally comprised closed proprietaryequipment supplied by a single manufacturer. With this type ofproprietary system, the installation, servicing and future modificationsof the component devices in the system were restricted to a singlemanufacturer's product offering and technical capability. In addition,it was very difficult or impossible to integrate new technologydeveloped by other manufacturers. If technology from other manufacturescould be integrated, it was usually too costly to consider.

Thus, it is desirable to create an open control system wherebyindividual sensors, processors and other components share informationamong one another. A few of the benefits of using an open system includereduced energy costs, increased number of design options for thefacility manager, lower design and installation costs since the need forcustomized hardware and software is greatly reduced and since starconfiguration point to point wiring is replaced by shared media andlastly, system startup is quicker and simpler.

In addition, expansion and modification of the system in the future isgreatly simplified. New products can be introduced without requiringmajor system redesign or reprogramming.

An integral part of any automation control system are the sensors andtransducers used to gather data on one or more physical parameters suchas temperature and motion. It would be desirable if a plurality ofsensor functions could be placed in a single device, fit in a standardsingle wall box opening and be able to communicate with one or morecontrol units, i.e., processing nodes, on the control network.

The number and types of sensors in this device could be many includingmultiple, dual or singular occupancy and security sensing via meansincluding passive infrared, ultrasonic, RF, audio or sound or activeinfrared. In addition, other multiple or singular transducers may beemployed such as temperature sensor, relative humidity sensor, ambientlight sensor, CO sensor, smoke sensor, security sensor, air flowsensors, switches, etc.

The utility of such a multifunction sensor can best be described by anexample. In order to minimize the number of unique devices that areinstalled in a room, it is desirable to have a sensor device reliablyperform as many functions as possible as this reduces the wiring costsas well as the number of devices required to be installed on the wallsof the room. Additionally, from an aesthetic point of view, architectsare under increasing demand by their clients to reduce the number ofunique sensor nodes in any given room.

Further, it is also desirable to have these transducers or sensorscommunicate with a microprocessor or microcontroller that can be used toenhance the application of the transducer. This may be accomplished byproviding the necessary A/D functions, including sensitivity and rangeadjustments of the transducer functions, and also by enabling the sensedinformation to be communicated over a bus or other media using asuitable protocol.

Further, calibration, either in the field or the factory could beemployed to generate either a relative or real absolute temperaturereading. Further, the control of any HVAC equipment could be performedeither locally at the sensor node or at a remote location. Also, thesensor devices could be used to control the lights in and outside theroom and building, control the HVAC controls in and outside the room andbuilding, send signals to or control the fire alarm and security alarmsystems, etc.

It is also desirable to enable the device to communicate using any ofthe standard protocols already in use such as Echelon LonWorks, CEBus,X10, BACNet, CAN, etc. Some examples of the media include twisted pair,power line carrier, optical fiber, RF, coaxial, etc.

The device thus preferably can transmit data or commands, receive dataor commands, activate and switch local or remote loads or controldevices, use and/or generate real time or relative readings, becalibrated externally in an automatic self adjusting way, calibratedexternally or via an electronic communications link. The ability tocommunicate over a network allows the user or network manager theflexibility to set light levels, temperature and humidity levels in thebuilding to desired levels either for maximizing the energy savings orfor the occupants comfort or convenience or for some combination of thetwo.

Additionally, the device preferably is able to minimize or eliminateeffects from its internal circuitry that may interfere with thetemperature reading of the temperature sensor.

Also, the device preferably has the ability to detect if there areadverse air flows emanating from the mounting hole in the wall or othersurface which could cause erroneous temperature and humiditymeasurements.

It is desirable if the device is mounted in a location that is exposedto the air in the environment of the room or area being monitored. Themotion detector transducer and sensor circuit is preferably mounted in amanner such that it is not exposed to (1) the air flow from theenvironment being monitored and (2) the air flow which may be createdwhen the device is mounted in or on a hole in the wall. Further, thehole in the wall is often created when the device is mounted on a wallin a home or office building. The hole may function to create a chimneyeffect given the right conditions. It is thus desirable to mount thetemperature sensor in a way which offers some shielding or insulationfrom direct exposure to heating or air ducts as well as any otherundesirable heating or cooling sources such as direct sunlight, fans,HVAC ducts, etc.

SUMMARY OF THE INVENTION

The present invention is a multifunction sensor and thermostat devicethat provides various transducer functions and the ability to controltemperature. In particular, the device comprises a means for performingtemperature sensing and control, humidity sensing, ambient lightsensing, motion detection, switching, relay control, dimming functionsand a means to put the device in an on, off or auto mode. The device canoptionally employ a cool/off/heat and fan on/auto switch that places theheating and cooling equipment in the appropriate state. Alternatively,it can perform these functions over the network via software control.Additionally, the device can also interface with master or slavethermostats and can turn on and off all types of fans (including ceilingand tabletop fans), heating units and cooling units. The device can alsobe linked to the on/off ‘kill’ switch commonly used for boilers and hotwater heaters. This ensures that the heating unit stays off in thesummer months. Such a device has utility in environments such as thatfound in offices, schools, homes, industrial plants or any other type ofautomated facility in which sensors are utilized for energy monitoringand control, end user convenience or HVAC control.

Key elements of the present invention include (1) overcoming thedifficulty of mounting diverse sensors or transducers within the samedevice or housing, (2) permitting these various sensors to exist in asingle package that can be mounted to a wall in a substantially flushmanner, (3) an embodiment that eliminates the requirement of an air flowchannel in the device, thus minimizing any adverse effects on the motiondetecting element or sensor as well as providing built in partialhysteresis and practical latency, and (4) an embodiment that utilizes anair flow channel in the device for drawing air over a temperature sensorand/or humidity sensor.

A prime objective of the present invention is to provide a flush orsurface mounted temperature, humidity and motion detection sensor in asingle device. The device may include additional transducers or sensorsand, in one alternative embodiment, is constructed such that thetemperature and humidity sensors are neither exposed to the flow of airin a room or area nor in an airflow channel whereby a chimney effect mayoccur. To avoid these conditions from occurring, the temperature andhumidity sensing elements are placed in a cavity that is coupled to theenvironment. Thus, the temperature and humidity of the air in the cavitychanges via diffusion with the temperature and humidity in thesurrounding environment. In addition, the temperature and humiditysensing elements, e.g., passive or active infrared sensor, is mounted soas to be shielded from exposure to direct sunlight and so as not to beexposed to a flow of air from the environment being monitored.

Further, the vents provided for the temperature and humidity sensingelement function as a baffle to provide hysteresis. The hysteresisprovides additional utility for the device in that the temperature andhumidity sensing elements are mounted within, beneath, part of, or onthe housing in such a way that the chimney effects due to airflow in thewall or from heating or cooling ducts nearby are reduced or eliminatedin a fashion that is similar to a ‘smoothing’ or softening affect andcan be adjusted mechanically and/or electronically through hardware orsoftware such that the hysteresis can be ‘settable’ to any achievablevalue and could even approach zero hysteresis if desired. Note that thetemperature and humidity sensor modules can be incorporated in a flushmount device, wall or surface mount device or ceiling device. Further,since an air channel is not required or used the device can be mountedflush in a single or multiple gang electrical box.

Another objective of the present invention is to provide a means oftemperature sensing utilizing multiple technologies including RTD, PRTD,thermisters, digital temperature sensors, PWM sensors, silicon sensors,capacitive and polymer sensors, etc. One or more sensors can be used inthe circuits that are coupled to a microprocessor or microcontroller.The sensor is positioned in a modular temperature chamber that permitsthe temperature sensor to acclimate to the ambient air temperature inthe surrounding environment. Access to the temperature sensor is simplyachieved by removal of a cover or panel without the need for specialtools.

Another objective of the present invention is to provide a means ofhumidity sensing utilizing one or more technologies including theDunmore Sensor, polymer capacitive type, carbon type, digital humiditysensors, automatic chilled mirror type sensors, silicon sensors, oxideand IR hygrometer sensors, etc. One or more sensors can be used in thecircuits that are coupled to a microprocessor or microcontroller. Thesensor is positioned in a modular temperature chamber that permits thehumidity sensor to acclimate to the ambient air conditions in thesurrounding environment. Access to the humidity sensor is simplyachieved by removal of a cover or panel without the need for specialtools.

The microcontroller is utilized to provide the capability oftransmitting and receiving real time data, relative data and actualdiscrete data in addition to switching and controlling loads locally orremotely. Data can be sent and received from other devices that are partof the distributed or centralized control system wherein devicescommunicate with each other using standard protocols such as EchelonLonWorks, CEBus, X10, BACNet, CAN, etc. The media utilized may comprisetwisted pair, power line carrier, RF, optical fiber, coaxial, etc.

The device also has the capability of self-calibration of the sensorsunder either local or remote control. For example, if the device isexposed to two different known temperatures, then the equation of a lineincluding the slope and relative offset connecting the two points can begenerated. This procedure can be performed once and either actual orrelative readings can be calibrated within the operating range of thedevice. In addition, points can be recorded and used to provideadditional accuracy or to extend the range of the temperature sensor.Further, a piece-wise linear, logarithmic or other arithmetic equationand look up table can be generated which is used to linearize theaccuracy or sensitivity of the temperature sensing element andassociated circuitry and to provide for sensing over a largertemperature or humidity range. In addition, local test resistors orpotentiometers can be used to adjust the range, sensitivity or accuracyof the sensor. A similar procedure can be used for calibration of thehumidity sensor.

Another key element of one alternative embodiment presented herein, isthat the temperature and humidity sensors do not have airflow channelthat permits air to circulate through the sensor module housing. Rather,the device has a passive alcove or cavity that acclimates to the ambientair temperature and humidity through the process of diffusion. Inaddition, the device incorporates a vent that permits any heat generatedby electronics or components to escape without adversely affecting thetemperature sensor and passive infrared sensor. In addition, thispermits any chimney effects generated by the hole in the wall to bemeasured by the device.

The device incorporates a temperature sensor transducer and sensingcircuit that is mounted in the sensor device housing in a location thatis exposed to the air in the room but not to air circulating internallywithin the device housing. A passive or active infrared sensor orultrasonic sensor is also mounted within the device housing with orwithout an insulating layer of material or conformal coating locatedsuch that it is not adversely affected by the venting of heat generatingcomponents or the chimney effects generated by the mounting hole and thevent.

The device also comprises airflow vents on the top of the device housingto provide a venting means for any components that generate heat withinthe device. These vents also provide airflow from the mounting hole orthe channel between the studs commonly found behind a wall within abuilding or wall. This flow of air provides for additional cooling ofheat generating components in the device and ensures that thetemperature and motion detection sensors are not adversely effected bythis airflow.

Optionally, a sensor could be used to measure this air flow which couldsubsequently be used for building maintenance purposes, i.e., to notifythe building owner of the location of air leaks within the walls of thebuilding. Note that in most buildings, insulation is placed in the wallof a building to reduce the hot or cold air losses thus saving utilityexpenses. In this case, the device can be used to detect and measure theairflow that occurs in a wall and notify building personnel that a wallin which the device is mounted does not have adequate insulation and/oris not properly sealed. The vents could also be provided on any othersurface of the device including opposite side surfaces or the bottom ofthe housing to provide additional or alternate venting.

In another embodiment, the device provides airflow channels that connectvents on the outer surface of the device to the chamber housing thetemperature and humidity sensing elements. Airflow is directed into thewide vents on the outer surface, over the temperature and humiditysensing elements and up the channels to exits from the vent opening onthe upper portion of the device.

The device also may include provisions for surface wiring and varioustypes of mounting means. Included as well is an optional positive screwmounting. The mounting means could be directly on a wall, on a modularfurniture channel or on or in a single gang wall box. The electricalconnections can be made using flying leads, terminal blocks, bindingscrews, or an RJ-11 or RJ-45 jack.

A lens is positioned in front of the infrared detector to focus infraredradiation and to prevent the ambient air from entering the device eitherfrom the temperature and humidity chamber or the heat vent. The lens mayor may not include blinders.

Optionally, the front PC board containing the passive infraredtransducer and the temperature and humidity sensors is installed using alayer of glue, foam or other gasket material to isolate the temperatureand humidity sensor transducers and the infiared sensor from the backboards and the air channel created by the heat vent and the hole in thewall.

Optionally, two infrared sensing elements can be mounted on the sameside of the printed circuit board. Partitioning of the two sensors canbe performed arbitrarily as long as the passive infrared sensor is notexposed to erroneous air flows created by a natural or artificial airchannel from the vents in the housing, the hole in the wall or the ventsfor the temperature chamber. Further, the motion sensing transducer ispreferably not exposed to airflow or any other environmental conditionsthat could cause adverse behavior to the performance of the device. Thetemperature and humidity sensors are isolated with the absence ofairflow over or around the infrared sensor. The housing is constructedsuch that it provides a chamber permitting the temperature and humidityto adjust naturally to the ambient air temperature and humidity to whichit is exposed by the process of diffusion. This is accomplished by theuse of the housing and a cover plate that is positioned over thetemperature and humidity sensing elements. Foam or insulating materialmay optionally be used since the temperature and humidity elements arenot in a channel where air is circulating, but rather is in an alcovechamber that acclimates to the environment.

In another optional embodiment, the passive or active infrared andtemperature and humidity sensors are on opposite sides of the printedcircuit board or on different boards such that the air around thetemperature and humidity sensors and the passive or active infraredsensor are isolated from one another by the nature of their location.

The device may incorporate at least one vent on the face of the deviceto allow the ambient air outside to acclimate with that of thetemperature and humidity chamber. Thus, the temperature and humiditysensors may be located centrally behind the vents or louvers or anywherewithin the area. In addition, the sensitivity, range, response time andaccuracy may be adjusted mechanically, via the use of different housingand vent shapes and materials and also by electronic means. The ventsare also constructed to be a protective cage for the sensors. Grooves inthe plastic and other means can be used to hold and/or align the sensorsas well.

Further, the device may incorporate adjustable louvers or vents over thetemperature and humidity sensors to create a baffle or regulator toadjust how quickly or slowly the temperature and humidity transducerswill adjust to the ambient air. Also, the sensitivity, range, responsetime and accuracy can be adjusted by adapting the layout, position anddesign of the vents or louvers. It is also within the scope of theinvention that mechanical or electronic means may be provided that openor close shutters on the vents over the temperature and humiditysensors.

Optionally, the device may incorporate fixed vents over the temperatureand humidity sensors that create a fixed baffle or regulator thusdetermining a fixed means for how quickly or slowly the temperature andhumidity transducers will adjust to the ambient air. The sensitivity,range, response time and accuracy, however, can still be adjusted byusing different materials, thickness and shapes and by locating thesensor in different locations and orientations.

In another optional embodiment the device does not incorporate any ventsand the temperature sensors is attached to the cover. In this case, theoutside ambient air will be measured by measuring the inside surfacetemperature of the cover or plate. Therefore, the temperature sensingtransducer is not directly exposed to any outside air. Also, thesensitivity, range, response time and accuracy may be adjusted usingdifferent materials, thickness and shapes and by locating the sensors indifferent locations or orientations.

In yet another optional embodiment of the invention the device does notincorporate vents and the temperature sensor is mounted on the surfaceof the device or in an alcove and exposed directly to the air. Theoutside ambient air is measured by measuring the air temperature of theoutside air. Therefore, the temperature sensing transducer is directlyexposed to the outside air. In addition, the sensitivity, range,response time and accuracy may be adjusted using different materials,thickness and shapes and by locating the sensors in different locationsor orientations.

Also, heat sinks can be added or connected to the sensor body and/or theleads and brought out of the device so as to improve the overalltemperature response of the transducer and the device.

In still another optional embodiment of the invention the device doesnot incorporate vents and the temperature sensor comprises a cover onthe device or a portion of the cover of the device and exposed directlyto the air. The temperature-sensing element can also be eitherpredominately outside, part of a cover or inside a cover of the device.This allows for very thin sensing materials to be used that are placeddirectly on the surface of the device, embedded in the layers of thecover of the device or predominately located on the inside portion ofthe cover of the device. The outside ambient air temperature is measuredby measuring the air temperature of the outside air. Therefore, thetemperature sensing transducer is directly exposed to the outside air.

In addition, the sensitivity, range, response time and accuracy may beadjusted using different materials, thickness and shapes and by locatingthe sensors in different locations or orientations. Although thetemperature sensing element and housing can take on various forms, someof the types are enclosed. A software algorithm can be optionallyemployed which functions to correct the hysteresis by adjusting theactual temperature reading and hence approximating the theoreticalresponse of a highly calibrated thermocouple. Additionally, thealgorithm can employ programmed undershoots, overshoots, delays,amplitude shifts and a variety of other signal manipulations.

Additionally, since the temperature sensor may be exposed to the openair, a ‘fast change algorithm’ can be employed which functions torecognize a rapid rate of change of temperature at the sensor, e.g.,more than 15 degrees per. 10 seconds or alternatively, that the slope,i.e., rate of change, of the temperature reading relative to time isgreater or less than some absolute value. The rapid temperature changemay either be due to someone placing their finger on the sensor,applying a heat gun, applying a cold compress or may be due to flamesfrom a fire. The software routine, in response to the detection of arapid rate of change in temperature, can either send a warning messageover the network or ignore the change in temperature, regarding it as anartificial heat/cold source. The device can be programmed to respondeither way, i.e., sending temperature data over the network and havingit acted upon or internally filtering it out and ignoring it.

Also, hardware and software can be employed to increase the sensitivityand accuracy of certain temperature and humidity ranges. For example,consider the temperature sensor circuitry having a temperature range of0 to 50 degrees. Also, assume it is broken into segments that arepiecewise linear, logarithmic or represented by some other mathematicalrelationship. For example, one range spans from 0 to 15 degrees C.,another from 15 to 30 degrees C. and the last from 30 to 50 degrees C.

To achieve increased accuracy within a span, for example, the 15 to 30degree range, a user would select this range over the network andsoftware means would provide greater resolution in that particular rangewhile sacrificing some resolution in the other ranges. This allows forusers to choose a certain temperature range to be processed at a higheraccuracy and the other ranges to be monitored using less accuracy. Thiscan be implemented via software and/or hardware by utilizing twodifferent circuits, each having different accuracy's for the thermistorand different gains for the electronics.

In another embodiment the cover over the temperature and humiditysensors is removable. The cover can be adapted to either require or notrequire a tool for removal. Alternatively, the cover can be fixablyattached to the device. In either embodiment, the temperature andhumidity sensing transducers and/or other components of the sensingcircuits are in a socket which permits replacement with anothertransducer or component with different parameters. In addition, anylocal components such as potentiometers, switches, etc. requiringadjustment can be accessed, adjusted or changed.

In one embodiment of the invention the software may be adapted to adjustthe sensitivity, response time, accuracy, range, etc. of the temperatureand humidity sensor elements and associated circuitries. In anotherembodiment, at least one air vent is provided which exposes both sidesof the back PC board to the potential airflow generated when electricalcomponents generate heat. In addition, the temperature and humiditychamber may be located in different parts of the device such ascentrally or at the top or bottom.

The device may be mounted using a variety of means. These includevarious mounting plate variations including mounting in a single ormultiple gang box, mounting on or in the hole of a modular furniturechannel, raceway, or being hung from underneath a fluorescent orincandescent fixture that is mounted on the desk, wall, floor or modularfurniture and mounting on any other suitable surface. In addition, thedevice contains ‘mouse holes’ which allow surface wiring to exit thedevice.

Another mounting option includes a hinged mounting bracket that permitsthe device to be mounted and electrically connected relatively easily.The mounting means uses either a positive locking screw or a snap fit.The positive locking screw option makes the device more tamperproof. Thesnap fit option provides a more aesthetically pleasing package.

Another optional feature is the use of a press to release button toallow for the device to be easily removed from the wall. This allows forthe device with its lighting and temperature sensor and controls to beremoved from its fixed position on the wall and moved freely about theroom. It can be placed in a more desirable location or can be used as aremote control as well as a regular wall mounted or table top switch ordimmer, sensor or thermostat as well as to adjust and control allnatural and artificial lighting, temperature and humidity devices.

The multi-sensor device of the present invention forms part of thenetwork control system and generally comprises the following basicelements: (1) user interface and controls, (2) power supply and mediaconnections, (3) communications media and protocol (4) load switching ordimming elements and (5) one or more sensor inputs.

Additionally, functions can be performed which include some type ofannunciation either by sound by using a buzzer or by sight by employingLEDs or controlling the lights in the room. For example, if the smokedetector transducer detects a fire, a buzzer could perform localannunciation. Alternatively, it could illuminate a visual indication oract as a ‘notification appliance,’ e.g., specially designed lights,LEDs, etc. for people that are hearing impaired. Also, a signal can besent to a control unit or lamp actuator to flash one or more lights inthe event that fire is detected for the benefit of the hearing impaired.

The power supply component for some of the devices in the system mayinclude means to operate from 100 to 347 VAC. This type of devicesupplies a nominal output voltage between 8 and 26 VDC and 8 to 24 VAC.Alternatively, the device may omit a power supply that converts utilitypower but rather is adapted to receive power from another device thatdoes incorporate a power supply that operates from 100 to 347 VAC. Themeans for distributing the electrical power to other devices could beaccomplished via any suitable means including twisted pair cabling,electrical power line cables or any other power carrying media.

Another key feature of the system is a communications media and protocolthat together form a communications network allowing messages to becommunicated (1) between devices within the system and (2) betweendevices located within the system and devices located external to thesystem. The messages comprise, among other things, commands forcontrolling and/or monitoring signals. These messages could be tightlycoupled, loosely coupled or of a macro broadcast nature. In addition,they may be one way simplex, half or full duplex bi-directional, withestablished priorities or without. The network communications medium maycomprise, for example, twisted pair Category 5 cabling, coaxial cabling,a standard POTS line, power line carrier, optical fiber, RF or infrared.The medium may be common or it may be shared with the possibility ofrequiring the use of gateways, routing devices or any other appropriatenetwork device for carrying data signals.

Depending on the type of network medium in use in the system, thedevices within the system include, within their housings, a slot thatallows for the connection of a bus terminator. The bus terminator istypically an RC network that is connected to the device and serves tomechanically as well as electrically connect the device to the networkcommunication line, e.g., twisted pair, coaxial, optical fiber, etc.

Thus, the system is able to communicate to devices within the system toprovide intrasystem control and monitoring as well as to communicateoutside the system to provide intersystem control and monitoring. Dataand/or commands are received and transmitted, real time relativereadings can be received and transmitted, devices can be calibratedexternally in an automatic self adjusting way or via a communicationlink over the network.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, withreference to the accompanying drawings, wherein:

FIG. 1 is a front view illustration of a first embodiment of thesensor/thermostat unit of the present invention incorporating PIR,temperature, humidity and ambient light sensors, thermostat control anda single switch;

FIG. 2 is a perspective view illustration of the sensor/thermostat unitof the present invention shown in FIG. 1;

FIG. 3 is a front view illustration of the sensor/thermostat unit of thepresent invention with the upper and lower covers removed;

FIG. 4 is a perspective view illustration of the sensor/thermostat unitof the present invention with the upper and lower covers removed;

FIG. 5A is a perspective view illustrating the upper portion of thesensor/thermostat unit in more detail wherein the PIR sensor blinds arein the open position;

FIG. 5B is a cross sectional view illustrating the upper portion of thesensor/thermostat unit in more detail wherein the PIR sensor blinds arein the open position;

FIG. 6A is a perspective view illustrating the upper portion of thesensor/thermostat unit in more detail wherein the PIR sensor blinds arein the closed position;

FIG. 6B is a cross sectional view illustrating the upper portion of thesensor/thermostat unit in more detail wherein the PIR sensor blinds arein the closed position;

FIG. 7 is a perspective view illustrating the temperature and humiditysensors and associated pedestal, housing and cover in more detail;

FIG. 8A is a perspective view illustrating the temperature and humiditysensor pedestal in more detail;

FIG. 8B is a side cross section view of the temperature and humiditysensor pedestal;

FIG. 9 is a front view illustration of a second embodiment of thesensor/thermostat unit of the present invention incorporating twoswitches and having the upper and lower covers in place;

FIG. 10 is a front view illustration of a third embodiment of thesensor/thermostat unit of the present invention incorporating twoswitches and having the upper and lower covers in place;

FIG. 11 is a perspective view illustration of a fourth embodiment of thesensor/thermostat unit of the present invention, a surface mountsensor/thermostat unit incorporating a single switch and having theupper and lower covers in place;

FIG. 12 is a front view illustration of a fifth embodiment of thesensor/thermostat unit of the present invention incorporatingtemperature and humidity sensors in an air flow chamber, air flowchannels, thermostat functions and a single switch;

FIG. 13 is a front view illustration of the sensor/thermostat unit ofFIG. 12 with the switch cover plate removed;

FIG. 14 is a rear view illustration of the sensor/thermostat unit ofFIG. 12 showing the embedded air flow channels for channeling air overthe temperature and humidity sensors;

FIG. 15 is a front view illustration of a sixth embodiment of thesensor/thermostat unit of the present invention incorporatingtemperature and humidity sensors in a diffusion chamber, thermostatfunctions and a single switch;

FIG. 16 is a front view illustration of the sensor/thermostat unit ofFIG. 15 with the switch cover plate removed;

FIG. 17 is a perspective view illustration of a seventh embodiment ofthe sensor/thermostat unit of the present invention incorporating adisplay, dimming brighten/dim control, temperature control andtemperature/room brightness display;

FIG. 18 is a schematic diagram illustrating the multifunction sensor andcontrol unit of the present invention;

FIG. 19 is a schematic diagram illustrating the motion sensor circuitryportion of the multi-sensor unit in more detail;

FIG. 20 is a schematic diagram illustrating the ambient light sensorcircuitry portion of the multi-sensor and control unit in more detail;

FIG. 21 is a schematic diagram illustrating the temperature sensorcircuitry portion of the multi-sensor and control unit in more detail;

FIG. 22 is a schematic diagram illustrating the humidity sensorcircuitry portion of the multi-sensor and control unit in more detail;

FIG. 23 is a block diagram illustrating the communications transceiverportion of the multi-sensor and control unit in more detail;

FIG. 24 is a schematic diagram illustrating the relay driver circuitryportion of the multi-sensor and control unit in more detail;

FIG. 25 is a schematic diagram illustrating the ballast dimmingcircuitry portion of the multi-sensor and control unit in more detail;

FIG. 26 is a schematic diagram illustrating the dimming circuitryportion of the multi-sensor and control unit in more detail;

FIG. 27 is a block diagram illustrating the software portion of themulti-sensor unit in more detail;

FIG. 28 is a diagram illustrating the relationship between the actualand measured lux versus light intensity;

FIG. 29 is a flow diagram illustrating the read temperature sensorportion of the software in more detail;

FIGS. 30A and 30B are a flow diagram illustrating the processtemperature value portion of the software in more detail;

FIG. 31 is a flow diagram illustrating the set point adjustment portionof the software in more detail;

FIG. 32 is a flow diagram illustrating the thermostat portion of thesoftware in more detail; and

FIG. 33 is a flow diagram illustrating the fast change portion of thesoftware in more detail.

DETAILED DESCRIPTION OF THE INVENTION Notation Used Throughout

The following notation is used throughout this document. Term DefinitionAC Alternating Current BACNet Building Automation and Control Network (adata communication protocol) CAN Controller Area Network CEBus ConsumerElectronics Bus CO Carbon Monoxide EEPROM Electrically ErasableProgrammable Read Only Memory EIA Electronic Industries Association HVACHeating Ventilation Air Conditioning IR Infrared LED Light EmittingDiode PC Printed Circuit PIR Passive Infrared POTS Plain Old TelephoneService PRTD Platinum Resistance Temperature Detector PWM Pulse WidthModulation RAM Random Access Memory RC Resister/Capacitor RF RadioFrequency ROM Read Only Memory RTD Resistance Temperature Detector SNVTStandard Network Variable Type

General Description

The present invention comprises a multifunction sensor and controldevice incorporating a plurality of sensors, one or more switches, aswitching dimming or 0-10 V dimming control and a thermostat function.The sensors comprise a motion detector, temperature sensor, humiditysensor and ambient light sensor. The motion detector may comprise anysuitable type of device capable of detecting motion such as PIR,ultrasonic or microwave. The temperature sensor is exposed to thesurrounding air via one of two ways: (1) being located within air flowchannel set up within the device or (2) being located within a chambersealed off from the rest of the device but exposed to the surroundingair via diffusion. In one embodiment, the passive infrared device usedfor motion detection is isolated from the air circulating for thepurpose of temperature measurement by the use of a lens surrounding themotion detector. In addition, the temperature sensor is placed within achamber isolated from the motion detector.

The temperature and motion detection sensors may reside on the same oropposite sides of a PC board. If they reside on the same side apartition isolates the two transducers since the temperature sensor isrequired to have airflow while the passive infrared sensor should not.

In one embodiment of the invention, the temperature and humidity sensorsare in an air channel or exposed to airflow, i.e., there is a separateentrance and exit of air having an associated speed, direction andforce. In another embodiment of the invention, no airflow channels areutilized. In this embodiment, the device employs the concept oftemperature diffusion with natural or artificial hysteresis by beingexposed to the ambient air and changing in a deliberately slower andlagging manner. This necessitates that no air channel or flow existsfrom one end of the device to the other.

This embodiment does not require the channeled circulation or flow ofair over the temperature sensor that can be analogized to the water flowin an aqueduct that flows in a directional manner with varyingdirections, speeds and volumes. This embodiment, on the other hand,measures temperature in a tidal fashion similar to the way the water inan ocean or harbor moves in and out from the shore. In other words, inone case air is flowing in a channel from one point to another similarto the way water flows in an aqueduct. In the case of this particularembodiment, the air moves in and out of the same opening like that ofthe rise and fall of the water in a harbor wherein the point of entryand exit for the air is the same.

The phenomenon can also be described as the process of diffusioninvolving the intermingling of air molecules from outside the device andthat of the air around the temperature sensor. Therefore, thetemperature sensor and the passive infrared sensor could reside on thesame or opposite sides of the PC board. The temperature and passiveinfrared elements, however, are required to be isolated from anyerroneous air flow channels that may be present which could affect theaccuracy of the measurements. Thus, the present invention provides apractical solution allowing temperature sensing and PIR motion sensingto reside in the same housing in a device that can be mounted in asingle gang box.

A front view illustration of a first embodiment of the sensor/thermostatunit of the present invention incorporating PIR, temperature, humidityand ambient light sensors, thermostat control and a single switch isshown in FIG. 1. The device, generally referenced 10, comprises ahousing 14 connected to a mounting plate 12 via one or more fastenersthrough apertures 35. The housing 14 comprises an aperture covered by alens or window 16. The aperture is used to house an occupancy sensor,e.g., passive infrared sensor (PIR). Note that the occupancy sensor maycomprise one or more PIR detectors, e.g., dual PIR detectors.

An upper cover 18, which may or may not be removable, is positionedbelow the motion detection element lens 16. Making the cover 18removable permits access to adjusting levers or blinds within the devicethat can be used to adjust the field of view of the PIR detectors in thedevice.

Below the cover 18 is a display 41 for displaying information such astemperature, status, commands or other type of data including but notlimited to the time of day including whether it is AM or PM and a timerdisplay letting the occupant know when the lights will time out. Thedisplay may comprise any suitable display type such as LCD, LED, plasma,etc and may or may not be backlit. Below the display 41 are two buttons43 for inputting information into the device 10. One button isconfigured as an up arrow and the other button is configured as a downarrow. These buttons could be used for example to set the desiredtemperature using the thermostat feature of the present invention.

A lower cover 28 functioning as a switch cover or plate having a raisedbar portion 32 is located below the display 41 and up/down arrow buttons43. The switch is used to control a logical load that the device isbound to or one of the internal load switching or dimming elements. Thelogical load comprises one or more physical electrical loads. Whenpressed, a message is sent to the control device connected to the loadto be switched. The message is interpreted and the control devicecarries out any required action. Note that the switch in this and allembodiments disclosed herein may comprise any suitable switch includingbut not limited to a mechanical pushbutton type switch, electricalrocker type switch, mechanical rocker type switch and an electronicswitch such as a touch plate or screen.

An aperture 26 is located within the switch cover 28 and may optionallyinclude a transparent or translucent window or light pipe therewithin.The aperture 26 provides visual access to a visual indicator such as anLED. The visual indicator is used to provide feedback to the user, e.g.,in connection with the status of the bound logical electrical load orthe status of occupancy as determined by the PIR sensor. The aperture 26also provides a light path for an optional ambient light sensor. Theambient light sensor measures the ambient light level that may be usedin determining the intensity of light to provide in the surroundingarea.

The device 10 also comprises a switch 30 that provides the user a meansfor placing the device into one or more modes. Typically, the switch 30comprises three positions: ON, AUTO and OFF. The ON position turns thelogical load on regardless of other inputs, the AUTO position lets theload be controlled by one or more sensor inputs and the OFF positionturns the load off regardless of the state of the sensor inputs.

The device 10 also incorporates an aperture, vent or grill 22 thatfunctions to allow air to diffuse through to an inner chamber housingthe temperature sensor 48 and humidity sensor 49.

Apertures 33 at the top and bottom of the mounting plate 12 provide ameans by which the device may be installed in a single or multiple gangwallbox. Apertures are also included to permit a cover plate (not shown)to be mounted over the device after it is installed in a wallbox.

When the device 10 is installed, for example in a wall, the hole in thewall required for the passage of wiring can either blow or suck air dueto the chimney effect. The housing comprises openings in specificplaces, e.g., only on the top, so as to direct any potential airflowthrough an area that will not impact the operation of the electroniccircuitry. If openings are placed on the top and bottom or not providedat all, this causes air to find its way in or out of the device throughincidental openings in the face. This would cause air to flow over theelectronic circuitry thus giving false readings, positive or negative.

A perspective view illustration of the sensor/thermostat unit of thepresent invention shown in FIG. 1 is shown in FIG. 2. A large portion ofthe housing 14 is shown including the fasteners 35 for connecting themounting plate 12 onto the housing 14. Shown are the occupancy sensorlens 16, upper cover 18 permitting access to the adjustable blinderswithin, display 41, up/down buttons 43, switch cover 28 including raisedbar 32 and light pipe 26, vent or aperture 22 for permitting thediffusion of air to the temperature and humidity sensors and apertures33 for affixing the device in single or multiple gang wallbox. Note thatin this view, the on/auto/off switch 30 is not visible.

A front view illustration of the sensor/thermostat unit of the presentinvention with the upper and lower covers removed is shown in FIG. 3.The device is shown with the upper cover 18 having been removed from thehousing 14. Visible now are the housing panel 50 and left and rightadjusting levers 44, 46, respectively. Also shown are the mounting plate12, mounting holes 33, PIR detector lens 16, display 41, up/down buttons43, grill aperture 22, humidity sensor 49, temperature sensor 48,fasteners 35 and mode switch 30. As with the upper cover, the lowercover or switch cover 28 has been removed revealing the housing panel 50and a series of indicators and switches. A visual indicator 31 such asan LED and an ambient light sensor 37 are located behind the aperture 26in the switch cover 28 such that light is able to reach the ambientlight sensor and the LED is visible from the outside.

Also shown is the tactile momentary switch 39 that is actuated by theswitch cover 28 when pressed by a user, a visual indicator 40, e.g.,LED, functioning as a LonWorks status LED and a momentary switch 42 thatfunctions as a LonWorks service request pin.

The blinders themselves are located behind the housing panel 50. Theadjusting levers 44, 46, however, extend beyond the surface of thehousing panel 50 so as to be accessible to a user. The blinders can beadjusted by moving the adjusting levers left or right along a linearpath in the housing panel 50.

A perspective view illustration of the sensor/thermostat unit of thepresent invention with the upper and lower covers removed is shown inFIG. 4. The removable upper cover 18 is shown oriented in a removedposition from the device 10. Tabs 25 on either side of the cover 18secure it to the housing 14. The removable lower cover or switch cover28 is also shown oriented in a removed position from the device 10.Pivots 23 on the top portion of both sides of the switch cover secure itto the housing 14. The pivot notches mate with corresponding mountingpoints in the housing panel 50. The switch cover 28 is shown also withthe aperture 26 and press bar 32. LEDs 31, 40, ambient light sensor 37and switches 39, 42 are also shown on housing panel 50.

Located in the lower portion of the device 10 is the vent grill 22having openings to permit the temperature and humidity sensors tocontact the surrounding air. The inner chamber formed within the devicebehind the grill is adapted so that it seals off the temperature andhumidity sensors from the inner space between the housing panel 50 andthe inner area of the device.

The grill 22 is shown with openings that are in a vertical fashion.Note, however, that they may be positioned horizontally, vertically orat any angle. The angle of the vent openings, however, could affect theresponse of the temperature and humidity sensing elements by allowingeither a more rapid rate of change or a slower rate of change based uponthe size, quantity, angle and shape of the openings. This change in thearchitecture of the vent 22 can be compensated for in the hardwareand/or software of the device. The optimum design for maximumperformance depends on the given application and desired temperature andhumidity changes per time period.

A perspective view illustrating the upper portion of thesensor/thermostat unit in more detail wherein the PIR sensor blinds arein the open position is shown in FIG. 5A. The adjusting levers 44, 46are shown in their widest open position, i.e., the adjusting levers arepositioned closest to the housing panel 50. In this position, the PIRdetectors are exposed to the largest area through the lens 16. Anillustration of the cross sectional cut 51 is shown in FIG. 5B. The dualPIR detectors 60, 62 are fastened to a mounting block 63, which in turnis fixed to the printed circuit board 61. The lens 16 is fixed to thehousing 14. The housing 14 is fastened to the mounting plate 12.

A partition or separating wall 76 functions to separate the radiationfalling on the two detectors 60, 62, reducing interference effects aswell as providing mechanical support in the event a foreign object ispressed against the lens. Two blinders 45, 47 functions to adjust theamount of radiation falling on the detectors 60, 62. Blinder 45comprises an elongated shutter section 74 supported by a lower wall 66and an upper wall (not shown) and a cylindrical stud or pivot 70.Similarly, blinder 47 comprises an elongated shutter section 72supported by a lower wall 64 and an upper wall (not shown) and acylindrical stud 68. The shutters are pivotally mounted to permit theblinders to be opened and closed. The blinders pivot on an axis formedby the cylindrical studs 68, 70.

The blinders may be curved and are preferably constructed of a materialthat does not pass the signal the detectors are adapted to respond to.The shutter sections may comprise a natural or synthetic rubber,thermoset or thermoplastic material or any other suitable molded ormachinable material. The material used is preferably moldable plastic.

A perspective view illustrating the upper portion of thesensor/thermostat unit in more detail wherein the PIR sensor blinds arein the closed position is shown in FIG. 6A. The adjusting levers 44, 46are shown in their narrowest closed position, i.e., the adjusting leversare positioned furthest away from the housing panel 50. In thisposition, the PIR detectors are exposed to the smallest area through thelens 16. An illustration of the cross sectional cut 53 is shown in FIG.6B. The blinders 45, 47 are shown in their most closed position. In thisposition, the largest amount of radiation coming through the lens 16 isblocked from falling on the detectors 60, 62.

Note that each of the blinders 45, 47 is independently adjustable sothat the angles that each blinder is set to may be equal or unequal. Tonarrow the field of view of the detectors, the blinders 45, 47 arerotated towards the partition 76. Vice versa, to broaden the field ofview of the detectors, the blinders 45, 47 are rotated away from thepartition 76. A more detailed description of the operation andconstruction of the blinders and the housing may be found in U.S. Pat.No. 5,739,753, entitled Detector System With Adjustable Field Of View,similarly assigned and incorporated herein by reference.

The mounting of the temperature sensor within the housing will now bedescribed in more detail. A perspective view illustrating thetemperature and humidity sensors and associated pedestal, housing andcover in more detail is shown in FIG. 7.

For clarity sake, a cutaway drawing is shown focusing on the grill andtemperature sensor assembly wherein the majority of the device has beenomitted. The plurality of electrical leads 90 from the temperaturesensor 48 are mounted on the PC board 80 via soldering or other means.The temperature sensor is mounted on a cylindrically shaped pedestal 82that extends from the surface of the PC board to the base of the sensor48. The electrical leads 90 of the temperature sensor 48 are insertedinto corresponding openings on the upper surface of the pedestal 82. Thecircular cutout in the housing panel 50 is constructed to snugly fitaround the diameter of the pedestal 82. An upper wall 83 is providedthat extends from the housing panel 50 to the outer cover. The upperwall helps to seal the temperature sensor from the rest of the device.

In accordance with the present invention, the outer cover, upper wall83, housing panel 50 and pedestal 82 are constructed and positioned soas to seal off the temperature sensor from the rest of the device. Thus,an air chamber is formed in which the sensor is positioned which permitsair from outside the device to diffuse through the vent 22 to the sensor48. Thus, the sensor is not exposed to any internal air channels thatmay be present and is separated from the PIR detectors so that they donot interfere with one another.

The pedestal will now be described in more detail. A perspective viewillustrating the temperature and humidity sensor pedestal in more detailis shown in FIG. 8A. A side cross section view of the temperature andhumidity sensor pedestal is shown in FIG. 8B.

As described above, the pedestal 82 functions to support the temperaturesensor 48 at a height above the PC board and also functions toenvironmentally isolate the sensor from the interior of the device.

The pedestal comprises a cylindrical body 100 and has a hollow interior.One end of the body 100 is closed off thus forming an upper portion. Theupper portion comprises a substantially flat surface 94 with a pluralityof apertures 96 therewithin. The flat surface 94 is recessed and adaptedto mate with the bottom surface of the temperature sensor and is shapedin accordance therewith. Surrounding the flat portion is a circularraised rid ge 98 extending around the entire circumference of thepedestal. A circular lip 93 is formed between the ridge 98 and the outerwall of the body 100.

The pedestal is positioned such that the lip 93 sits flush against theinterior edge of the housing panel 50 (see FIG. 7). The ridge 98 isadapted to fit snuggly within the inner diameter of the cutout in thehousing panel. Thus, the pedestal functions to seal the sensor from aircirculating within the device between the PC board 80 and the housingpanel 50. It is important to note that other shapes for the temperaturesensor are also possible other than the one shown here. Regardless ofthe type or shape of the sensor, the upper surface portion of thepedestal should be adapted to mate with the sensor to enclose it thussubstantially forming a seal around the bottom portion of the sensor asshown herein.

A second embodiment of the multi-sensor device will now be presented.The first embodiment discussed above, incorporated multiple sensors anda thermostat function with a single switch. The second embodimentpresented herein incorporates two switches. A front view illustration ofa second embodiment of the sensor/thermostat unit of the presentinvention incorporating two switches and having the upper and lowercovers in place is shown in FIG. 9. The device, generally referenced110, is similar to device 10 of FIG. 1 with the difference being thattwo switches are included rather than one. This embodiment is usefulwhen it is desired to control two separate logical loads from a singledevice in on/off fashion.

The device comprises a mounting plate 12, housing 14, lens 16 for thePIR detectors, a removable cover 18, display 41, up and down buttons 43and grill 22 permitting air to diffuse through to the temperature sensor48 and humidity sensor 49. A first switch cover 122 and a second switchcover 124 are provided having optional raised bumps 127 to help usersdistinguish the two switches from each other by way of tactile feel,such as when operating the switch in low light or darkness. Also shownare the mode switch 30 which can be placed in an on, auto or offpositions and the light pipe 126 which provides a light path to aninternal LED or other light source and an ambient light sensor.

A third embodiment also splits the switch cover 28 (FIG. 1) into twoseparate covers as the device of FIG. 9. A front view illustration of athird embodiment of the sensor/thermostat unit of the present inventionincorporating two switches and having the upper and lower covers inplace is shown in FIG. 10. The device of FIG. 10, however, provides adimmer function for one or more electrical loads. The switch cover 123,when pressed, functions to brighten the load as indicated by the uparrow 129 and conversely, when the switch cover 125 is pressed, the loadis dimmed, as indicated by the down arrow 121.

Similar to the device of FIG. 9, the device comprises a mounting plate12, housing 14, lens 16 for the PIR detectors, a removable cover 18,display 41, up and down buttons 43 and grill 22 permitting air todiffuse through to the temperature sensor 48 and humidity sensor 49.Also shown are the mode switch 30 which can be placed in an on, auto oroff positions and the light pipe 126 which provides a light path to aninternal LED or other light source and an ambient light sensor.

A fourth embodiment comprises a sensor unit similar to that of FIGS. 1and 2 but suitable for mounting on a surface of a wall. A perspectiveview illustration of a fourth embodiment of the sensor/thermostat unitof the present invention, a surface mount sensor/thermostat unitincorporating a single switch and having the upper and lower covers inplace is shown in FIG. 11. The device, generally referenced 400,comprises a surface mount housing 402 and can be mounted to a wall box.The features and functionality of the device 400 are similar to those ofdevice 10 (FIG. 1) and have been described hereinabove. Note thatcorresponding elements have been given the same reference numerals toaid the reader in understanding the invention.

A front view illustration of a fifth embodiment of the sensor/thermostatunit of the present invention incorporating temperature and humiditysensors in an air flow chamber, air flow channels, thermostat functionsand a single switch is shown in FIG. 12. This device, generallyreferenced 410, comprises a housing and front face portion 412. The faceportion includes a display 414 for displaying information such astemperature, status, commands or other type of data. The display maycomprise any suitable display type such as LCD, LED, plasma, etc. Belowthe display 414 are two buttons 416 for inputting information into thedevice 410. One button is configured as an up arrow and the other buttonis configured as a down arrow. These buttons could be used for exampleto set the desired temperature using the thermostat feature of thepresent invention.

A slide switch 417 is provided for selecting between cool, heat or off.An additional slide switch 419 is employed on the other side of thedisplay 414 that functions to allow the fan controls to be placed in anAUTO or ON state. Both slide switches are optional. If the device 450functions as a master thermostat then it is desirable to have the slideswitches. On the other hand, if the device 450 is in an officeenvironment, for example, it may not be desirable to have the slideswitches.

Another optional feature is the use of a press to release button (notshown) to allow for the device to be easily removed from the wall. Thisallows for the device with its lighting and temperature sensor andcontrols to be removed from its fixed position on the wall and movedfreely about the room. It can be placed in a more desirable location orcan be used as a remote control as well as a regular wall mounted ortable top switch or dimmer, sensor or thermostat as well as to adjustand control all natural and artificial lighting, temperature andhumidity devices.

Artificial devices include all type of conventional HVAC cooling andheating devices. Natural devices include but are not limited to suchdevices as ceiling fans, windows, window shades, skylights, etc., i.e.,devices other than conventional HVAC devices.

A switch 420 is located below the display 414 and up/down arrow buttons416. The switch is used to control a logical load that the device isbound to. The logical load comprises one or more physical electricalloads. When pressed, a message is sent to the control device connectedto the load to be switched. The message is interpreted and the controldevice carries out any required action. On either side of the upperportion of the switch 420 is a vent opening 422 that leads to an innerair flow channel running downwardly to the chamber behind the grill 426.

A visual indicator 424 such as an LED or light bar is positioned belowthe switch 420. The visual indicator is used to provide feedback to theuser, e.g., in connection with the status of the logically boundelectrical load. The device 410 also incorporates an aperture grill orvent 426 located below the LED 424. The vent 426 functions to allow airto diffuse through to an inner chamber housing the temperature sensor430 and humidity sensor 428. The chamber is connected via air channelswithin the device that run up inside the face cover 412 of the deviceand exit through the vent openings 422 situated on either side of theswitch 420.

The device 410 also comprises a switch (not shown) that provides theuser a means for placing the device into one or more modes. The switchmay include two modes: OFF and AUTO. The AUTO position lets the load becontrolled by one or more sensor inputs and the OFF position turns theload off regardless of the state of the sensor inputs.

Apertures 421 at the top and bottom of side face extensions 418 providea means by which the face cover 412 device may be fastened to a housing,the housing being adapted to be installed in a single or multiple gangwallbox. Apertures (not shown) are also included to permit a cover plate(not shown) to be mounted over the device after it is installed in awallbox.

Note that the use of air channels in this embodiment of the invention,precludes the incorporation of PIR motion detection sensors in thedevice due to the problems associated with obtaining false readings ofthe PIR sensors. The problems arise due to the channeled air flowingnear the PIR sensing elements. In addition, this embodiment may or maynot comprise an ambient light sensor. The device 410 shown in FIG. 12does not show one, however, an ambient light sensor may be placed behindthe grill 426 or behind the switch cover 420 using a translucent windowto permit light from outside the device to reach the ambient lightsensor.

A front view illustration of the sensor/thermostat unit of FIG. 12 withthe switch cover plate 420 removed is shown in FIG. 13. The area 432behind the switch cover 420 houses a plurality of switches and visualindicators. A tactile momentary switch 434 is mechanically coupled tothe switch cover 420 when it is in place. A user actuates the switch 434by pressing on the switch cover 420. A visual indicator 438, e.g., LED,functions as a LonWorks service status LED, i.e., node statusindication. LEDs 424 and 438 may optionally be different colors such asred for LED 424 and yellow for LED 438. A momentary switch 440 functionsas a combination LonWorks compatible service request/go unconfiguredbutton. A switch 436 functions as an off/auto button.

The off/auto button 436 is used to place the device 410 into the offstate or the auto state. In the off state, the device ceases to respondto sensor input including switch closures and will not transmit messagesonto the network to other devices. When the device is in the auto state,it responds to sensor input and to switch closures and transmitsmessages to other nodes on the network.

The service request/go unconfigured button 440 performs two functions.When the service request/go unconfigured button 440 is pressedmomentarily, e.g., for one second, the device 410 performs normalservice pin functions. However, when the service request/go unconfiguredbutton 440 is pressed for more than a certain period of time, e.g., sixseconds, the device will be placed into the unconfigured state. Thus, auser may issue a command to the device, via the button 440 thatfunctions as an input means, telling it to enter the unconfigured state.The software controlling the button can be adapted to not place thedevice in the unconfigured state if the command is continuously presentwithout interruption at the input means. The operation of the gounconfigured feature is described in detail in U.S. patent applicationSer. No. 09/080,916, filed May 18, 1998, entitled “Apparatus For AndMethod Of Placing A Node In An Unconfigured State,” incorporated hereinby reference.

A rear view illustration of the face of the sensor/thermostat unit ofFIG. 12 showing the embedded air flow channels for channeling air overthe temperature and humidity sensors is shown in FIG. 14. The rear sideof the face cover 412 comprises an air channel 442 grooved into the facecover that extends from the vent openings 422 downward along the outeredges of the switch cover to the hollowed out chamber area 444 that liesbehind the grill 426. In operation, air enters the device 410 via thelarger grill openings, over the temperature and humidity sensors, up theair channels 442 and out the vents 422. The channels 442 and the entireairflow chamber can be completely enclosed in the plastic frame or mayalso use a combination of the printed circuit board, housing, gasketsand other elements to create an air flow channel.

A front view illustration of a sixth embodiment of the sensor/thermostatunit of the present invention incorporating temperature and humiditysensors in a diffusion chamber, thermostat functions and a single switchis shown in FIG. 15. In this embodiment, the device, generallyreferenced 450, comprises an air diffusion chamber to expose thetemperature and humidity sensors to the surrounding air, rather than theair channels of the device 410 of FIG. 12.

The device 450 is similar to that of the device of FIG. 12 with theremoval of the vent openings and the widening of the switch cover. Inparticular, the device 450 comprises a housing and front face portion452. The face portion includes a display 454 for displaying informationsuch as temperature, status, commands or other type of data. Below thedisplay 454 are two buttons 456 for inputting information into thedevice 450. One button is configured as an up arrow and the other buttonis configured as a down arrow. These buttons could be used for exampleto set the desired temperature using the thermostat feature of thepresent invention.

A slide switch 457 is provided for selecting between cool, heat or off.An additional slide switch 459 is employed on the other side of thedisplay 454 that functions to allow the fan controls to be placed in anAUTO or ON state. Both slide switches are optional. If the device 450functions as a master thermostat then it is desirable to have the slideswitches. On the other hand, if the device 450 is in an officeenvironment, for example, it may not be desirable to have the slideswitches.

A switch 462 is located below the display 454 and up/down arrow buttons456. The switch is used to control a logical load that the device isbound to. The logical load comprises one or more physical electricalloads. When pressed, a message is sent to the control device connectedto the load to be switched. The message is interpreted and the controldevice carries out any required action.

A visual indicator 464 such as an LED or light bar is positioned belowthe switch 462. The visual indicator is used to provide feedback to theuser, e.g., in connection with the status of the bound logicalelectrical load. The device 450 also incorporates an aperture grill orvent 466 is located below the LED 464. The vent 466 functions to allowair to diffuse through to an inner chamber housing the temperaturesensor 470 and humidity sensor 468.

Apertures 460 at the top and bottom of side face extensions 458 providea means by which the face cover 452 device may be fastened to a housing,the housing being adapted to be installed in a single or multiple gangwallbox. Apertures (not shown) are also included to permit a cover plate(not shown) to be mounted over the device after it is installed in awallbox.

Note that this embodiment may or may not comprise an ambient lightsensor. The device 450 shown in FIG. 15 does not show one, however, anambient light sensor may be placed behind the grill 466 or behind theswitch cover 462 using a translucent window to permit light from outsidethe device to reach the ambient light sensor.

A front view illustration of the sensor/thermostat unit of FIG. 15 withthe switch cover plate 460 removed is shown in FIG. 16. The area 472behind the switch cover 462 houses a plurality of switches and visualindicators. Situated within the area 472 are a tactile momentary switch474, a visual indicator 476, e.g., LED, which functions as a LonWorksservice status LED, i.e., node status indication, a momentary switch 478which functions as a combination LonWorks compatible service request/gounconfigured button and a switch 480 which functions as an off/autobutton. The operation of switches 474, 478, 480 and LED 476 is identicalto those of switches 434, 440, 436 and LED 438, respectively, of FIG. 13as described in detail hereinabove.

A perspective view illustration of a seventh embodiment of thesensor/thermostat unit of the present invention incorporating a display,dimming brighten/dim control, temperature control and temperate/roombrightness display is shown in FIG. 17. This is another alternative forthe face cover portion that may be incorporated into the multi-sensordevice of the present invention. The device, generally referenced 130,is shown installed with a cover plate in a single gang wallbox. Theelements visible comprise a cover plate 140 that surrounds the device,an up/down dimming control 134, a temperature display 138, a brightnessdisplay 136 and a grill 135 for a temperature sensor and/or humiditysensor located between them. The grill 135 is similar in constructionand function to grill 22 as shown in FIGS. 1 and 2 and describedhereinabove.

The temperature display 138 is shown in degrees Fahrenheit but can bealso displayed in degrees Celsius. The temperature control 132 providesa means for a user to enter information such as temperature set pointsfor the thermostat function. The dimming control 134 can provide notonly a brighten/dim function but also an on/off function as well. Notethat the device 130 may function only as a control and display device oralternatively, may incorporate the temperature sensor, humidity sensor,ambient light sensor and occupancy sensor of the embodiments describedhereinabove.

The present invention is intended to function within a local operatingnetwork or network based control system incorporating multiple deviceshaving different functionality. As an example, the local operatingnetwork can be applied to lighting and HVAC systems. The local operatingnetwork comprises one or more devices, a user interface, actuatorelement, power supply, communications media, media connections andprotocol and sensor inputs. These components function to work togetherwith other devices that can communicate using the same standardcommunication protocol to form a local operating network. The systemcomprises various device functionality including but not limited tovarious sensor and transducer functions such as motion detector sensors,temperature sensors, humidity sensors and dimming sensors. The devicesmay be packaged in various form factors including but not limited tosurface mount, flush mount, wall mount and single or dual gang wall boxand ceiling mount. Other features include light harvesting or constantlight maintenance, time of day scheduling, on/off/auto switching andsensing, single and multiple 20 A 100 to 347 VAC switching devices forincandescent and fluorescent lighting loads and 8 A 800 W 100 to 347 VACdimming triac devices with a series air gap relay element. The devicescomprise software and/or firmware for controlling the operation andfeatures of the device, 15 VDC power supply for supplying electricalpower for the 0-10V dimming signal, a reset push button for resettingthe device and a communications network media interface.

To aid in understanding the principles of the present invention, theinvention is described in the context of the LonWorks communicationprotocol developed by Echelon Corp. and which is now standard EIA 709.1Control Network Protocol Specification, incorporated herein byreference. Other related specifications include EIA 709.2 ControlNetwork Powerline Channel Specification and EIA 709.3 Free TopologyTwisted Pair Channel Specification, both of which are incorporatedherein by reference.

The scope of the present invention, however, is not limited to the useof the LonWorks protocol. Other communication network protocols such asCEBus, etc. can be used to implement a control network within the scopeof the present invention.

A key feature of the system is that the devices on the network caninteroperate over the network. In addition, the system can be expandedat any time, and the functionality of the individual components can bechanged at any time by downloading new firmware.

For a device to be interoperable it must communicate in accordance withthe protocol specification in use in the system, e.g., LonWorks, CEBus,etc. If a device complies with the standard or protocol in use, it cancommunicate with other devices in the system. The temperature sensorwithin the device may be bound (as defined by the LonWorks protocol) tothe HVAC system, for example. After a threshold temperature is exceeded,the temperature sensor can respond by sending a command to the HVACsystem to turn on the air conditioning.

A schematic diagram illustrating the occupancy, ambient light, switch,dimmer, temperature and humidity unit (also referred to generally assimply the ‘unit’) of the present invention is shown in FIG. 18. Theunit 150 comprises a controller 190 to which are connected variouscomponents. The controller 190 comprises a suitable processor such as amicroprocessor or microcomputer. In the context of a LonWorks compatiblenetwork, the controller may comprise a Neuron 3120 or 3150microcontroller manufactured by Motorola, Schaumberg, Ill. More detailedinformation on the Neuron chips can be found in the Motorola Databook:“LonWorks Technology Device Data,” Rev. 3, 1997, incorporated herein byreference. Memory connected to the controller includes RAM 200, ROM 202for firmware program storage and EEPROM 204 for storing downloadablesoftware and various constants and parameters used by the unit.

A power supply 172 functions to supply the various voltages needed bythe internal circuitry of the device, e.g., 5 V (V_(CC)), 15 V, etc. Thepower supply 172 may be adapted to provide V_(CC) and other voltagesrequired by the internal circuitry either directly from phase andneutral of the AC electrical power source or from an intermediatevoltage generated by another power supply. For example, a 15 V supplyvoltage may be generated by another device and provided to the unit 150via low voltage cabling. This reduces the complexity of the unit 150thus reducing its cost by eliminating the requirement of having a highvoltage power supply onboard.

A clock circuit 170 provides the clock signals required by thecontroller 190 and the remaining circuitry. The clock circuit maycomprise one or more crystal oscillators for providing a stablereference clock signal. The reset/power supply monitor circuitry 168provides a power up reset signal to the controller 190. The circuit alsofunctions to monitor the output of the power supply. If the outputvoltage drops too low, the reset circuit 168 functions to generate areset signal as operating at too low a voltage may yield unpredictableoperation.

In the case of LonWorks compatible networks, the unit 150 comprises aservice pin on the controller 190 to which is connected a momentary pushbutton switch 156 and service indicator 154 which may comprise an LED.The switch 156 is connected between ground and the cathode of the LED154. The anode of the LED is connected to V_(CC) via resister 152. Azener diode 158 clamps the voltage on the service pin to a predeterminedlevel. The switch 156 is connected to the service pin via a seriesresister 174. The service pin on the controller functions as both aninput and an output. The controller 190 is adapted to detect the closureof the switch 156 and to perform service handling in response thereto. Amore detailed description of the service pin and its associated internalprocessing can be found in the Motorola Databook referenced above.

The unit 150 is adapted to interoperate with other devices on thenetwork. It incorporates communication means that comprises acommunication transceiver 192 that interfaces the controller 190 to thenetwork. The communications transceiver 192 may comprise any suitablecommunication/network interface means. The choice of network, e.g.,LonWorks, CEBus, etc. in addition to the choice of media, determines therequirements for the communications transceiver 192. Using the LonWorksnetwork as an example, the communications transceiver may comprise theFTT-10A twisted pair transceiver manufactured by Echelon Corp, PaloAlto, Calif. This transceiver comprises the necessary components tointerface the controller to a twisted pair network. Transmit data fromthe controller 190 is input to the transceiver which functions to encodeand process the data for placement onto the twisted pair cable. Inaddition, data received from the twisted pair wiring is processed anddecoded and output to the controller 190. In addition to a free topologytransceiver for a twisted pair network, other transceivers can be usedsuch as RS-232, RS-485 or any other known physical layer interfacessuitable for use with the invention. In addition, transceivers for othertypes of media such as power line carrier and coaxial, for example, canalso be used.

The unit 150 also comprises mode switch means that provides three modesof operation to the user: on/off/auto. The mode switch means comprisesslide switch 160, pull up resisters 180, 182, series resisters 176, 178and zener diodes 162, 164. The slide switch 160 is a three positionslide switch which has two of the its terminals connected to two I/Opins on the controller 150 via series resisters 176, 178. One comprisesthe ON mode state and the other the OFF mode state. Software in thecontroller 150 periodically scans the two I/O pins for the state of themode switch. The controller uses software adapted to decode the signaloutput of the mode switch to yield the actual switch position. The AUTOmode state is represented by both OFF and ON inputs being low.

The mode switch controls the operation of the unit 150. If the switch isin the OFF state, the on/off or brighten/dim features of the device aredisabled. If the switch is in the AUTO position, the device operatesnormally. When the mode switch is on the ON position, the load is forcedto turn on regardless of the state of the on/off/auto switch inputs.

As described hereinabove, the unit 150 is adapted to measuretemperature, humidity, ambient light and to detect occupancy. The unit150 comprises (1) motion sensor circuitry 194 that functions to generatea MOTION signal representing the level of motion; (2) ambient lightsensor circuitry 196 that functions to generate a LUX signalrepresenting the level of light; (3) temperature sensor circuitry 198that functions to generate a TEMP signal representing the temperaturelevel; and (4) humidity sensor circuitry 199 that functions to generatea HUM signal representing the humidity level. The four analog signalsMOTION, LUX, TEMP and HUM are input to a four-channel A/D converter 188.Mux control of the A/D converter 188 is provided by the controller 190.The digitized output of the A/D converter is input to an I/O port on thecontroller 190. Alternatively, the A/D conversion function may beincorporated into the controller as is common with many commerciallyavailable microcontrollers.

The unit 150 also comprises relay driver circuitry 490 coupled to one ormore relay loads; ballast dimming circuitry 510 coupled to one or more0-10 V ballast loads; and dimming circuitry 530 coupled to one or moredimming loads.

An occupancy detect indicator 186, which may comprise an LED, provides auser visual feedback as to the detection of motion by the unit. Thecathode of the LED 186 is input to an I/O pin on the controller 190 andthe anode is pulled high by pull up resister 184. An active low on thesignal OCCUPANCY_DETECT causes the LED to light.

The unit also provides a user the capability to either turn one or morelighting devices on/off and or to brighten/dim them. The unit 150comprises circuitry two momentary contact switches 218, 220 that areconnected to two I/O pins on the controller 190 via series resisters206, 208, respectively. One end of each switch is coupled to ground andthe other end is clamped by a zener diode 214, 216. The output of eachswitch is pulled high to V_(CC) via pull up resisters 210, 212.

The two switches 218, 220 may be installed in the unit behind a rockerpanel such that one switch is operated when one end of the toggle ispressed and the other switch is operated when the other end of thetoggle is pressed. Pressing on the upper portion of the toggle turns thelighting load on and pressing on the lower potion turns it off.Alternatively, the unit can be adapted to cause the lighting load tobrighten and dim in response to the toggle being pressed upwards ordownwards, respectively.

In connection with the embodiment shown in FIG. 1, the device 10 onlyrequires a single switch as this embodiment operates a single logicallighting load which could physically be many lighting loads. The switchplate 28 is adapted to operate only a single push button switch. Eachswitch closure toggles the state of the logical and physical lightingload.

In connection with the embodiment of FIG. 9, the device 110 requires twoswitches but each could operate a separate logical lighting load thatcould physically be many lighting loads. One switch plate 122 isassociated with one load and the other switch plate 124 is associatedwith the other load. Each switch closure for each of the two switchesfunctions to toggle the state of the respective logical and physicallighting load.

In connection with the embodiment of FIG. 10, the device 110 requirestwo switches for providing brighten/dim control for a single or multiplelighting load. One switch plate 123 is associated with the brightenfunction and the other switch plate 125 is associated with the dimfunction. In addition, the up switch plate may also turn the load on andthe down switch plate may function to turn the load off.

Thus, depending on the functionality desired in the device, the switchesand associated hardware circuitry and software application may beadapted to provide numerous lighting control possibilities.

The motion sensor circuitry will now be described in more detail. Aschematic diagram illustrating the motion sensor circuitry portion ofthe multi-sensor unit 150 in more detail is shown in FIG. 19. The motionsensor circuitry 194 comprises one or more passive infrared (PIR)sensors coupled between ground and V_(CC). In the example disclosedherein, two PIR sensors 230, 232 are connected between ground andV_(CC). The PIR sensors may comprise a single sensor unit such as partnumber LHI878 manufactured by EG&G Heimann Optoelectronics GmbH,Wiesbaden, Germany, or in the alternative a dual sensor unit. The signaloutput of PIR sensor #1 230 is processed by circuitry comprisingcapacitor 234 and resister 236. The signal is then input to a signalconditioning operation amplifier (op amp) circuit comprising op amp 242,capacitors 238, 244 and resisters 240, 245. The signal is input to theinverting input of the op amp 242.

The signal output of PIR sensor #2 233 is processed by circuitrycomprising capacitor 260 and resister 264. The signal is then input tothe non-inverting input of the op amp 242 via capacitors 264, 270 andresisters 266 and 268, 272 that form a voltage divider.

The output of the op amp 242 is input to a second signal conditioning opamp circuit comprising op amp 254, capacitors 246, 258, 252 andresisters 247, 256, 248 and 250. The output of the op amp 254, i.e., theMOTION signal, is input to the A/D converter 188 (FIG. 14). The digitalrepresentation of the level of motion is processed by the occupancy task(described in more detail below) to determine whether or not theoccupancy state should be declared.

A schematic diagram illustrating the ambient light sensor circuitryportion of the multi-sensor unit in more detail is shown in FIG. 20. Theambient light sensor circuitry 196 comprises an ambient light detector280 such as part number S1087 manufactured by Hamamatsu Photonics K.K.,Hamamatsu City, Japan. The cathode of the light detector 280 isconnected to the inverting input of op amp 286. The anode of thedetector 280 is connected to ground. A voltage reference V_(REF1) isinput to the non-inverting input of the op amp. Capacitor 284 andresistor 282 are placed in the feedback path from the output to theinverting input via a voltage divider connected to the output andconsisting of resisters 287, 288. The output of the op amp, i.e., theLUX signal, is input to one of the channels of the A/D converter 188.The digitized ambient light level is processed by the ambient lightlevel task (described in more detail below) and transmitted as a networkvariable to all devices over the network that are bound to the device.

A schematic diagram illustrating the temperature sensor circuitryportion of the multi-sensor unit in more detail is shown in FIG. 21. Thetemperature sensor circuitry 198 comprises a temperature sensor 290 suchas the NTC thermistor 23322-640-55103 manufactured by Philips. One sideof the NTC temperature sensor 290 is coupled to ground while the otherside is connected to resistor 291, which is of same resistance value andtolerance as the temperature sensor, forming a voltage divider whereby avoltage of 2.50 V (typically) represents a sensor case temperature of 25degrees C.

The voltage divider is formed between a 5 VDC power supply voltageconnected to resistor 291. The non-circuit ground side of the NTCtemperature sensor is input to the non-inverting input of op amp 298 viaseries resister 292 and resister 294 coupled to circuit ground. Ideally,resistors 292 and 294 approximate 0 ohms. The inverting input of op amp298 is connected to a voltage reference V_(REF2) (typically 2.5 VDC) viamatched voltage divider resisters 296 and 297 and is also connected tothe output via feedback resister 300.

Matching resistors 296 and 297 form a voltage divider that is connectedto the inverting input of op amp 298. Resistor 296 has one sideconnected to voltage reference V_(REF2) and the other side is connectedto resistor 297 that then connects to circuit ground.

Resisters 296, 297 and 300 are selected so as to provide a typical gainof 1, although other values of gain are also suitable. In other words,the output of the op amp 298 is fed back to the inverting input creatinga voltage follower circuit thus providing and overall gain of unity. Thegain of the op amp can be modified to increase the resolution of thetemperature reading over a given range. The output of the op amp, i.e.,the TEMP signal, is input to one of the channels of the A/D converter188. The digitized ambient light level is processed by the temperaturetask (described in more detail below) and transmitted as a networkvariable to all devices over the network that are bound to the device.

In an alternative embodiment, a dual op amp circuit may be employed. Inthis case, the temperature sensing circuitry is coupled to two separateop amps. One of the op amps provides a unity gain as in the op ampcircuit illustrated in FIG. 21 and the second provides a gain factorhigher than unity, e.g., 5, so as to provide a finer resolution reading.The unity gain op amp provides a 0 to 5 volt range corresponding to atemperature range of 0 to 50 degrees Celsius. The op amp with a highergain factor would provide a 0 to 5 volt range for a temperature rangeof, for example, 15 to 35 degrees Celsius.

Assuming a wide bit A/D converter is used, e.g., 16 bits, the upper 8bits can be used for an incremental reading of 1 degrees Celsius and thelower 8 bits can be used for a higher resolution reading of {fraction(1/100)} degree Celsius.

A schematic diagram illustrating the humidity sensor circuitry portionof the multi-sensor unit in more detail is shown in FIG. 22. Thehumidity sensor circuitry 199 is constructed around a humidity sensor660. A humidity sensor suitable for use with the present invention isthe EMD-2000 Micro Relative Humidity Sensor manufactured by GeneralEastern, Woburn, Mass. A suitable op amp is the LM358 whose outputcomprises the HUM. Signal input to the A/D converter block 188 (FIG.18).

A block diagram illustrating the communications transceiver portion ofthe control unit in more detail is shown in FIG. 23. As describedpreviously, the communications transceiver 192 functions to enable thecontrol unit to communicate with other devices over the network. It isdesirable that each device in the network incorporate communicationsmeans enabling it to share information with other devices. This is not,however, an absolute necessity as devices that do not employ acommunications protocol or employ a protocol that is proprietary canalso be part of the network. For example, a direct connection to thelighting load via a 0-10 VDC control line as well as a single analogoutput signal may be employed to communicate to one or more lighting andHVAC loads. In this example, the communications transceiver 192 isadapted to transmit and receive data over twisted pair wiring. Asmentioned previously, the communication transceiver could be adapted toother type of media as well including, but not limited to, power linecarrier, coaxial, RF, etc.

The communications transceiver 192 comprises a twisted pair transceiver222 for receiving Tx data from the controller and for outputting Rx datato the controller. In the transmit path, the twisted pair transceiverprocesses the Tx data received from the controller resulting in a signalsuitable for placement onto the twisted pair network. The Tx output ofthe twisted pair transceiver, which has been converted to a differential2-wire signal, is input to the twisted pair interface circuitry 224which functions to adapt the differential transmit signal to the 2-wiretwisted pair network 226.

In the receive path, the signal received over the 2-wire twisted pairnetwork 226 is input to the twisted pair interface circuitry 224. Theinterface circuitry functions to output a 2-wire differential receivesignal that is input to the twisted pair transceiver 222. The twistedpair transceiver 222 processes the differential receive signal andgenerates an output Rx signal suitable for input to the controller.

A more detailed description of the communications transceiver suitablefor twisted pair networks and for other types of network media can befound in the Motorola Databook referenced above.

A schematic diagram illustrating the relay driver circuit portion of themultifunction sensor and control unit in more detail is shown in FIG.24. The relay driver circuit 490 comprises a transistor circuit forcontrolling the coil 500 of a relay 502. The RELAY signal from thecontroller is input to the base of transistor 494 via resister 496 andresistor 492 connected to ground. The coil 500 is placed in parallelwith a diode 498 and connected between the 15 V supply and the collectorof transistor 494. The diode 498 functions to suppress the back EMFgenerated by the coil when it is de-energized. In accordance with theRELAY signal, the circuit functions to open and close the relay 502 thatis connected to the relay load.

A schematic diagram illustrating the ballast dimming circuitry portionof the multifunction sensor and control unit in more detail is shown inFIG. 25. The ballast dimming circuit 510 comprises an op amp 518 andassociated components which functions to output a signal in the range of0 to 10 VDC. The output signal causes fluorescent lights that areequipped with electronic ballasts to dim to a particular level. Theelectronic ballasts are adapted to receive a standard 0 to 10 V signalthat corresponds to the desired light intensity level. The electronicballast consequently adjusts the voltages applied to the bulbs they areconnected to in accordance with the level of the input ballast-dimmingsignal.

The pulse width modulated BALLAST signal from the controller is input tothe non-inverting input of the op amp 518 via the integrating filterrepresented by the series resister 512 and the capacitor 514 to ground.This signal is then amplified to an appropriate level via the op amp 518and its associated resistor network comprised of resistors 516 and 520.The resulting amplification of this particular circuit is approximatelygiven by the following expression, $1 + \frac{R_{138}}{R_{136}}$

A zener diode 522 prevents the ballast output signal from exceeding apredetermined value. Note that the control unit may comprise a pluralityof ballast dimming circuits for dimming a plurality of fluorescent lightloads.

A schematic diagram illustrating the dimming circuitry portion of themultifunction sensor and control unit in more detail is shown in FIG.26. The dimming circuitry 530 functions to control the light level of anincandescent load (a dimming load). The dimming circuitry 530 comprisestwo portions: a triac dimming portion and a relay portion. The triacdimming portion comprises a triac 542 that is turned on at differentpoints or angles of the AC cycle to effect the dimming function. Thetriac 542 is triggered by an opto coupled diac 536 which comprises anLED 534 optically coupled to a diac 540. The diac 540 is connected tothe gate of the triac 542. The DIMMING signal from the controller turnson the LED 534 whose anode is connected to V_(CC) via resister 532. TheDIMMING signal is brought low when the triac is to be turned on. Thetiming of the signal input to the opto coupled diac is synchronized withthe zero crossings of the AC power. While the dim level of the load isset to non zero, the DIMMING signal is applied on a periodic basis,i.e., every AC half cycle.

Across the anode and cathode of the triac 542 are connected a resister546, capacitor 544 and a pair of MOVs 562, 566. A coil 548 is located inseries with a capacitor 564 connected to the neutral of the AC power. Arelay 560 is placed in series with the triac for providing an air gapbetween the phase of the AC power and the load. The relay 560 iscontrolled by relay drive circuitry comprising transistor 572, resistors574, 576, diode 570 and coil 568. The relay drive circuitry shown hereoperates similarly to the relay drive circuitry of FIG. 24. When it isdesired to completely turn the load off, the controller asserts theDIM_RELAY signal which cause the relay 560 to open.

A block diagram illustrating the software portion of the multi-sensorunit in more detail is shown in FIG. 27. The hardware and softwarecomponents of the unit in combination implement the functionality of thedevice. The software portion of the unit will now be described in moredetail. Note that the implementation of the software may be differentdepending on the type of controller used to construct the unit. Thefunctional tasks presented herein, however, can be implementedregardless of the actual implementation of the controller and/orsoftware methodology used.

In the example presented herein, the controller is a Neuron 3120, 3150or equivalent. Some of the functionality required to implement thecontrol unit is incorporated into the device by the manufacturer. Forexample, the processing and associated firmware for implementing thephysical, link and network layers of the communication stack areperformed by means built into the Neuron processor. Thus, non-Neuronimplementations of the control unit would require similar communicationmeans to be able to share information with other devices over thenetwork.

It is important to note that some of the tasks described herein may beevent driven rather than operative in a sequential program fashion. Thescope of the invention is not limited to any one particularimplementation but is intended to encompass any realization of thefunctionality presented herein. In addition, some of the tasks areintended to function based on input received from other devices thatalso communicate over the network.

The various tasks described herein together implement the functionalityof the unit. Each of the tasks will now be described in more detail. Themain control task 310 coordinates the operation of the unit. The controltask is responsible for the overall functioning of the unit includinginitialization, housekeeping tasks, polling tasks, sensor measurement,etc. In general, the unit is adapted to measure one or more physicalquantities, transmit the measured quantities over the network, issuecommands to a control unit located on the network and respond tocommands received over the network from other sensors and controldevices.

The control is effected by the use of network variables referred to asStandard Network Variable Types (SNVTs), in the case of LonWorksnetworks, for example. Thus, the data transmitted over the network istransmitted in the form of one or more network variables. In addition,based on the values of the various network variables received by theunit, the unit responds and behaves accordingly. The following describesthe functionality provided by the unit.

The following functions: relay, occupancy, lumens maintenance, dimming,California Title 24, ambient light level, light harvesting, ballast,analog 0 to 10 V, reset, go unconfigured, communication I/O, inhibit andscenes are described in detail in U.S. patent application Ser. No.09/213,497, filed Dec. 17, 1998, entitled “Network Based ElectricalControl System With Distributed Sensing And Control,” incorporatedherein by reference.

Reset

The reset task 312 functions to place the controller into aninitialization state. Variables are initialized, states of the variousdrivers are initialized, memory is cleared and the device beginsexecuting its application code. The reset task executes at start up andat any other time it is called or the power is reset. The task functionsto initialize the internal stack, service pin, internal state machines,external RAM, communication ports, timers and the scheduler. Before theapplication code begins executing, the oscillators are given a chance tostabilize.

Inhibit

The inhibit task 314 provides the capability of inhibiting andoverriding the normal operating mode of the device and possibly one ormore other devices connected to the network. This task is intended tooperate within an electrical network that is made up of a plurality ofdevices wherein one or more of the devices is capable of commanding acontrol device to remove and reapply electrical power from a logicalload connected to it. The devices or nodes communicate with the controldevice over the communications network.

For example, in a network utilizing a plurality of sensors and a controlunit coupled to one or more logical loads, wherein each logical loadcomprises one or more physical electrical loads, one of the devicegenerates an inhibit signal that is communicated to the control unit.The control unit then propagates a feedback signal to the plurality ofsensors. The sensor devices may comprise any type of sensor such as anoccupancy sensor, switch or dimming sensor. Each sensor device is boundto its associated control unit. The one or more physical electricalloads are connected to the control unit. A feedback variable is boundfrom the control unit to each of the sensors.

When one of the sensors is turned off, i.e., its switch setting isplaced in the OFF position, the inhibit task is operative to inhibit thenormal operating mode of all the other input sensors and the controlunit. Note that the term ‘turning a device off’ includes switching thedevice off, disabling the device, placing the device in standby mode ortripping the device. There can be multiple sensor devices simultaneouslyin the off, disabled, standby or tripped mode. The control unit and itsload remain inhibited until all the sensor devices are no longer in theoff, disabled, standby or tripped mode. Thus, electrical power to theload controlled by the control unit remains disconnected until allsensor devices are in the on position.

This feature is particularly suited to permit maintenance or service tobe performed in a safe manner on (1) any of the sensors, i.e.,switching, occupancy, dimming, etc. sensor devices, logically connectedto the same control unit or on (2) the load physically connected to thecontrol unit.

The mode switch 160 (FIG. 18) is used for placing the unit into an off,disabled, standby, tripped or maintenance inhibit mode. The switch meanscan be implemented using mechanical or electronic means or a combinationof the two either at the device itself or remotely over a network viaone or more control commands. Optionally, a pull out tab or mechanicalarm can be used to put the input device into the maintenance off modewhen it is pulled out. The pull out tab or mechanical arm would leavethe input device in normal operating mode when pushed back in.

In either case, when the input device is placed in the off position, aninhibit message is sent to the control unit over the network. Inresponse, electrical power to the attached load is removed.Subsequently, all other sensor devices that are bound to the samecontrol unit are inhibited from causing power to be applied to the load.This permits safe access to the control unit and to the load for serviceor maintenance reasons. The normal operating mode of all the sensordevices connected to the same control unit is inhibited or overridden.Until all sensor devices that have previously been placed in the offmode are, put into the on mode and returned to their normal operatingcondition, all sensor devices are not permitted to change the state ofthe load or the control unit.

Further details on the implementation of the inhibit task can be foundin co-pending U.S. application Ser. No. 09/045,625, filed Mar. 20, 1998entitled “Apparatus For And Method Of Inhibiting And Overriding AnElectrical Control Device,” similarly assigned and incorporated hereinby reference.

Go Unconfigured

The go unconfigured task 316 provides the capability of placing a device(also refereed to as a node) in an unconfigured state. This is usefulwhenever the device needs to be placed in a certain state such as theunconfigured state. A major advantage of this feature is that itprovides an installer of LonWorks based systems the ability to easilyplace the electrical device (the node) in an unconfigured stateutilizing the same button 156 (FIG. 18) that is used in making a servicerequest.

When the device is in the configured node state (also known as thenormal operating mode state), the device is considered configured, theapplication is running and the configuration is considered valid. It isonly in this state that both local and network derived messages destinedfor the application software layer are received. In the other states,i.e., the application-less and unconfigured states, these messages arediscarded and the node status indicator 154 (FIG. 18) is off. The nodestatus indicator is typically a service light emitting diode (LED) thatis used to indicate to a user the status of the node.

A device is referred to as configured if it is either in the hardoff-line mode (i.e., an application is loaded but not running) or in theconfigured node state as described above. A node is consideredunconfigured if it is either application-less or in the unconfiguredstate, i.e., no valid configuration in either case. Via the gounconfigured task, a user can force the device into the unconfiguredstate so that it can be re-bound to the network, i.e., the device mustbe ‘reset’ within the LonWorks system.

More specifically, the term going unconfigured, is defined as having theexecution application program loaded but without the configurationavailable. The configuration may either be (1) not loaded (2) beingre-loaded or (3) deemed bad due to a configuration checksum error.

In a LonWorks device, an executable application program can place itsown node into the unconfigured state by calling the Neuron C built infunction ‘go_unconfigured( )’. Using this built in function, anapplication program can determine, based on various parameters, whetheror not an application should enter this state. When the device doesenter the unconfigured state, theNode Status Indicator flashes at a rateof once per second.

The unit of the present invention utilizes the service pin on thecontroller, e.g., Neuron chip, to place the node in an unconfiguredstate. Under control of the firmware built into the Neuron chip, theservice pin is used during the configuration, installation andmaintenance of the node embodying the Neuron chip. The firmware flashesan LED suitably connected to the service pin at a rate of ½ Hz when theNeuron chip has not been configured with network address information.When the service pin is grounded, the Neuron chip transmits a networkmanagement message containing its 48 bit unique ID on the network. Anetwork management device to install and configure the node can thenutilize the information contained within the message. The Neuron chipchecks the state of the service pin on a periodic basis by the networkprocessor firmware within the chip. Normally, the service pin is activelow.

Further details on the implementation of the go unconfigured task can befound in U.S. application Ser. No. 09/080,916, filed May 18, 1998 citedabove.

Communication I/O

The communication I/O task 318 functions in conjunction with thecommunication means located in the controller and the communicationtransceiver connected to the controller. The controller itself comprisesmeans for receiving and transmitting information over the network. Asdescribed previously, the communications firmware for enablingcommunications over the network is built into the Neuron chip. Furtherdetails can be found in the Motorola Databook referenced above.

Occupancy

The occupancy task 320 is used to detect occupancy and maintain theoccupied state until no occupancy is detected. The occupancy task 320implements the occupancy functionality of the unit. Typically, theoutput generated by the occupancy task is bound to a control unit orsimilar device, which controls electrical power to the load. Theoccupancy task performs the motion detection function and calculatesapplication delay and/or hold times as required. The SNVT‘SNVT_occupancy’ can be used in implementing the occupancy detection andreporting functions.

Along with the basic detection of motion, the occupancy task can utilizeone or more configuration parameters that function to control thedetection and reporting operations. In particular, a hold timeparameter, e.g., SNVT_time_sec nciHoldTime, can be set which delays thereporting of a change from the occupied to unoccupied state. Note thatpreferably the occupancy sensor changes from the unoccupied state to theoccupied state rapidly, but changes from the occupied to the unoccupiedstates after a delay. The purpose of the delay is to avoid unnecessarynetwork traffic when the occupancy sensor is not detecting motioncontinuously. This is particularly useful when PIR detectors areemployed in the sensor unit.

The occupancy task 320 functions to control a relay or dimming load inaccordance with the detection of motion in an area. One or moreoccupancy sensor devices can be bound to a relay or dimming objectwithin the controller. A network may include a plurality of occupancysensors and a control unit coupled to a load. Typically, the occupancysensors are bound via the network to the control unit. The load to beswitched or dimmed is coupled to the control unit. In a LonWorksnetwork, any number of sensors can be bound to the same object (load).The occupancy task does utilize any feedback from the control unit. Inaddition, more than one load can be connected to and controlled by thecontrol unit.

In addition, a light-harvesting feature (described in more detail below)can be enabled or disabled for each input. This feature utilizes thelight level sensed by an ambient light level sensor also connected tothe network. When occupancy is detected, the sensor functions togenerate a command that is sent to the occupancy task in the controlunit. The command is sent via the setting of a value for a particularnetwork variable. The occupancy task first checks the current level ofthe light. If light harvesting is enabled, the lights turn on inaccordance with the light-harvesting task. The ambient light level isperiodically checked and the brightness of the lights is adjustedaccordingly. If light harvesting is not enabled, then the lights areturned on in accordance with the following Lighting Priority Order:

-   -   1. If the last light level value was not equal to zero, i.e.,        completely off or 0%, then the level of the lights will be set        to the last dim level that was set at the time the lights were        last turned off.    -   2. If the last light level value was equal to zero but the        Preferred Level is not equal to zero then the level of the        lights will be set to the Preferred Level value. Note that it is        not desirable to set the lights to a 0% dim level, as confusion        may arise whether the device is operating properly, since 0% dim        appears as completely off.    -   3. If the last light level value was equal to zero and the        Preferred Level is null then the level of the lights is set to        maximum brightness, i.e., 100%.        Note that in each case, the light level is brought up the        required level in gradual increments, resulting in a gradual        turn on of the lighting load. The Preferred Level value (also        referred to as the Happy State) is a brightness level that is        calculated in order to reduce the number of writes to the EEPROM        connected to the controller. The Preferred Level is generated by        using a sliding check of the brightness levels set by the user        over time. The Preferred Level is set if the light is turned on        to the same brightness level a predetermined number of times        consecutively, e.g., 5 times. If the current level is equal to        the previous level the required number of times consecutively,        then that particular brightness level is stored in EEPROM and a        variable is set within the controller. The counter is reset once        a current level does not match the current level. Note that a        Preferred Level of zero is stored or permitted.

As described above, the analog signal MOTON output by the occupancysensor circuitry 194 (FIG. 19) is input to one of the channels of theA/D converter. The digitized value is then input to the controller whoreads it periodically. The MOTION signal is a bipolar analog signaladapted to the range of 0 to 5 V for input to the A/D converter. With a12-bit A/D converter, the MOTION signal is converted into a value from 0to 4196. The value 2300 is taken as the null motion level thatrepresents no detected motion.

The controller functions to generate a window with high sense and a lowsense values forming the boundaries of thresholds of the window. If theA/D value exceeds the high sense threshold or is lower than the lowsense threshold, occupancy is declared. The high and low sense valuesare variable depending on the field of view/sensitivity setting set bythe user. The values of the high and low sense thresholds for variousfield of view settings are presented below in Table 1. TABLE 1 Field OfView Low Sense High Sense Delta Δ High 1900 2700 ±350 On 1700 2900 ±500Medium 1300 3300 ±1000 Low 700 3900 ±2000 Off Occupancy Off

Thus, based on the field of view setting, occupancy is declared when theA/D value exceeds either the low or high sense thresholds. The largerthe field of view, the smaller the window size, i.e., smaller A/D valuescause occupancy to be declared. Conversely, the smaller the field ofview, the larger the window size, i.e., larger A/D values causeoccupancy to be declared.

After either the low or high sense threshold is exceeded, the A/D valueis tracked and the occupancy detect LED 186 (FIG. 18) is illuminated.Once the value falls back below either threshold, a delay timer isstarted. The length of the timer is adjustable and is relatively short,e.g., 50 to 100 ms. If the A/D value remains within the thresholdsettings for the entire timer duration, the occupancy LED isextinguished and a hold timer is started. The occupancy state is notchanged at this point and electrical power to the load is not removed.The hold timer counts a hold time duration that is settable over thenetwork by a user. Only after the hold time is reached without the A/Dvalue exceeding either threshold is the occupancy state removed and anetwork message is transmitted instructing the control unit to turn theload off.

For LonWorks based networks, the following output network variables maybe used in implementing the occupancy sensor function: occupancy,occupancy numerical output and occupancy auxiliary state. The followinginput network variables may be used: hold time, maximum send time andfield of view.

A key feature of the unit is that both the field of view and thesensitivity of the occupancy sensor can be adjusted over the network.Optionally, adjustments can be scheduled at either specific or randomtime intervals as determined by a scheduler device that transmitscommands to the unit. For example, the field of view can beautomatically adjusted over the network in accordance with the time ofday, time clock, scheduler or other devices or inputs such as a localset point button/slider or via a network management tool.

The field of view and the sensitivity of the occupancy sensor can bechanged by varying the threshold window that is used to process theMOTION signal (FIG. 19) output of the occupancy sensor circuitry. Thethreshold information may reside in non-volatile memory, e.g., EEPROM,and can be altered over the network. It may also be stored in RAM andchanged dynamically over the network. Different applications couldemploy the ability to adjust the field of view combined with the abilityto set different levels, different polarities such as negative orpositive response of the PIR, time frames or number of hits or cycles.

A user of the unit has the ability to select the desired field of viewlevel between high, on, medium, low and off, representing fields ofview >100%, 100%, 50%, 25% and off, respectively.

The occupancy sensor can be overridden, i.e., ignored, in response to ascheduled or random input. For example, occupancy may be ignored duringcertain times of the day such as during nighttime hours. A switch can bebound with the occupancy sensor to provide an override function to turnthe lights on at night or during off-hours. This feature is useful sincethe PIR detectors activate when they detect changes in heat or highlevels of energy which are often generated, for example, by walkietalkies. Thus, this feature functions to minimize the ‘false ons’ thatoccur then the HVAC system is turned off at night or on in the morning.

In addition, the unit may be adapted to require a sequence orcombination of multiple sensor input activity from one or more devicesin various locations before establishing that occupancy exists. Thisfunctions to reduce the effects of noise that may be present in theenvironment the unit is operative in.

Ambient Light Level

The ambient light task 322 functions to measure the ambient light leveland output the corresponding lux value. The ambient light task 322implements the ambient light functionality of the unit utilizing the LUXoutput of the ambient light sensor circuitry 196 (FIG. 20). The ambientlight level task functions to maintain a particular lux level within anarea, if the user enables this mode. The task receives ambient lightsensor data from an ambient light sensor bound to it over the network.The ambient light sensor periodically sends lux reading updates to theambient light level task. The lux level to be maintained is provided bythe user.

The ambient light level task operates in conjunction with the occupancysensor device and its related occupancy task. If an occupancy sensordetects motion, for example, the lights are controlled in accordancewith the current ambient light level reading. If the light level isgreater than or equal to the current maintenance lux level setting, thenthe lights are not turned on. If, on the other hand, the light level isgreater than or equal to the current maintain lux level setting, thenthe light is turned on in accordance with the Lighting Priority Orderdescribed above.

The ambient light sensor has the ability to detect different lightlevels and is self calibrated via the intrinsic gain in each device. Thesensors can be calibrated in the field by taking two ambient lightreadings and entering the values into a network management tool thatwould then adjust the processing algorithm to produce a more accuratereading.

One application of the ambient light feature is to maintain a particularlux level within an area. The ambient light task receives light leveldata from the ambient light sensor and transmits the lux readings to alldevices bound to it over the network.

The standard network variable SNVT_lux can be employed in theimplementation of the ambient light task. In addition to the basic luxlight level output, the light sensor object may input one or moreparameters. In particular, the parameters may include the following:

-   -   1. location (nciLocation)—physical location of the light sensor.    -   2. reflection factor (nciReflection)—used to adjust the internal        gain factor for the measured illumination level; this may be        necessary because the amount of light reflected back to the        sensor element from the surface might be different.    -   3. field calibration (nciFieldCalibr)—used by the light sensor        to self calibrate the sensor circuitry; the ambient light value        measured with an external lux meter is used as input to the        light sensor which then adjusts its reflection factor to yield        the same output value.    -   4. Minimum send time (nciMinSendT)—used to control the minimum        period between network variable transmissions, i.e., the maximum        transmission rate.    -   5. Maximum send time (nciMaxSendT)—used to control the maximum        period of time that expires before the current lux level is        transmitted; this provides a heartbeat output that can be used        by bound objects to ensure that the light sensor is still        functioning properly.    -   6. Send on delta (nciMinDelta)—used to determine the amount by        which the value obtained by the ambient light sensor circuitry        must change before the lux level is transmitted.        Note that these parameters are optional and may or may not be        used in any particular implementation of the ambient light task.

The ambient light sensor circuitry operates with an offset. A lightlevel of zero lux generates approximately 1.6 V at the output of the A/Dconverter. In addition, the sensor and its housing are adapted to besensitive to changes in light intensity on tabletops within the area tobe covered. The cover (lens) positioned over the sensor so that lightenters via the aperture 26 (FIG. 1) in the switch cover. Thisarrangement, however, functions to attenuate the light even more. Thus,an offset and a correction factor must be applied to values read fromthe sensor.

A value from the sensor is read in to the controller periodically, e.g.,every 100 ms. An average is computed for every 10 values read in. Thisnumber is then used to calculate a lux reading using the followingexpression,${lux\_ value} = {{conversion\_ factor} \cdot 1000 \cdot \left( {{average} - {offset}} \right) \cdot \left( \frac{\max({LUX})}{{\max({average})} \cdot 1000} \right)}$The above equation yields a LUX value in the range of 0 to 2,500 lux. Inaddition, a user can supply a reflection coefficient that can befactored into the calculation of the lux value. The reflectioncoefficient is expressed as a number in the range of +/−3.0. The luxvalue calculated using the equation above is multiplied by thereflection coefficient to yield a lux value compensated for reflections.

Further, a linearity correction (slope offset correction adjustment orcalibration factor) can be applied which typically varies from room toroom. Two light readings are taken, one in bright light and the other indim light. Two sets of readings are taken: one using the unit 150 andthe other set using an external sensor. The system installer can performthis procedure at the time the system is initially installed.

A diagram illustrating the relationship between the actual and measuredlux versus light intensity is shown in FIG. 28. The linearity correctionprocedure described above, compensates for this slope offset.

Temperature

The temperature task 324 functions to read the TEMP signals generated bythe temperature sensor circuitry 198 (FIG. 21). The TEMP value isconverted to digital by the A/D converter 188 and read into thecontroller 190. The temperature sensor circuitry is adapted to output aTEMP value corresponding to a temperature in the range of 0 to 50° C.Assuming an A/D with 0 to 5 V output range, a temperature of 25° C.corresponds approximately to 2.5 V at the output of the A/D converter.

In accordance with the TEMP signal read in, a temperature value iscalculated using the following,${temperature\_ value} = {1000 \cdot {TEMP} \cdot \left( \frac{2500}{2100 \cdot 1000} \right)}$The nonlinearity of the temperature sensor can be corrected for byapplying a calibration correction using slope and offset adjustments insimilar fashion as the occupancy task described above.

In addition, a standard network variable can be employed in theimplementation of the temperature sensor task. In addition to the basictemperature output, the temperature sensor object may input one or moreparameters. In particular, the parameters may include the following:

-   -   1. location (nciLocation)—physical location of the light sensor.    -   2. field calibration (nciFieldCalibr)—used by the temperature        sensor to self calibrate the sensor circuitry; the temperature        value measured with an external temperature sensor is used as        input to the temperature sensor which then adjusts its algorithm        to yield the same output value    -   3. Minimum send time (nciMinSendT)—used to control the minimum        period between network variable transmissions, i.e., the maximum        transmission rate    -   4. Maximum send time (nciMaxSendT)—used to control the maximum        period of time that expires before the current temperature        reading is transmitted; this provides a heartbeat output that        can be used by bound objects to ensure that the temperature        sensor is still functioning properly.    -   5. Send on delta (nciMi elta)—used to determine the amount by        which the value obtained by the temperature sensor circuitry        must change before the temperature reading is transmitted.        Note that these parameters are optional and may or may not be        used in any particular implementation of the temperature sensor        task.

As described above, the temperature sensor and software include anoffset calibration value that can be employed to calibrate thetemperature sensor. Also, the speed at which the temperature value issent over the network can be increased or decreased.

A flow diagram illustrating the portion of the software used to read thetemperature sensor in more detail is shown in FIG. 29. This process isperformed on a periodic bases, e.g., every 100 ms. An averagetemperature reading is calculated every 10 cycles, i.e., once a second,in order to reduce the effect of transients and random fluctuations.First, it is checked whether the OUTPUT_TEMP flag is set (step 330).This flag is set true at the end of a cycle of 10 readings. If the flagis true, then the accumulated temperature variable TEMP_VALUE is resetto zero (step 332), the counter TEMP_COUNT is reset to zero (step 334)and the OUTPUT_TEMP flag is cleared (step 336).

If the flag is not set, these steps are skipped and control passes tostep 338 wherein a temperature reading is input from the A/D converter(step 338). The value read in is added to TEMP_VALUE (step 340). Thecounter TEMP_COUNT is incremented (step 342). When the count reaches 10(step 344), the TEMP_SENSOR flag is set (step 346). If 10 temperaturevalues have not yet been read in, the process ends. Note that dependingon the controller used to implement the invention, the count may exceed10 such as when the event scheduler internal to the controller could notservice the event fast enough due to high loading.

A flow diagram illustrating the process temperature value portion of thesoftware in more detail is shown in FIGS. 30A and 30B. This routine isperformed whenever the TEMP_SENSOR flag is set. First, the temperaturereadings are averaged by dividing TEMP_VALUE by TEMP_COUNT (step 350).The OUTPUT_TEMP flag is set so that a new set of readings can beaccumulated (step 352). The digital number obtained for the average isconverted to an equivalent number in degrees Celsius (step 353). Afterconverting the average to degrees Celsius, one or more slope, offset andcorrective algorithm adjustments are then performed (step 354).

The difference T_(D) between the current temperature T_(C) and thepresent temperature T_(P) is then calculated: T_(D)=T_(C)−T_(P) (step355). The new current temperature T_(NC) is calculated by applying thedifference T_(D) as a percent increase or decrease. For example,T_(NC)=T_(C)+T_(D)−T_(C) (step 356). Over time the differencetemperature TD approaches zero (as does the slope of the rise or fall ofthe temperature relative to time) as the temperature begins to changemore slowly and the room reaches a stable ambient. At this point, T_(NC)will equal T_(C). The new current temperature is averaged to apredefined number of readings at a predefined interval taken over agiven time period (step 357). The average is stored as a newuncalibrated temperature (step 358).

It is then checked whether a TEMP_OFFSET update has been received overthe network (step 359). If so, a new calibration offset temperaturevalue is calculated (step 360). If no update has been received, thecurrent temperature is calculated using the calibration offset (step362).

If the current temperature is changing at a rate faster than apredetermined rate (step 363), then it is assumed that either a falseinfluence is occurring or a fire may exist in the vicinity of thedevice. As described previously, since the temperature sensor may beexposed to the open air, a ‘fast change algorithm’ can be employed whichfunctions to recognize a rapid rate of change of temperature at thesensor, e.g., more than 15 degrees per 10 seconds. The rapid temperaturechange may either be due to someone placing their finger on the sensor,applying a heat gun, applying a cold compress or may be due to flamesfrom a fire. The software routine, in response the detection of a rapidrate of change in temperature, can either send a warning message overthe network or ignore the change in temperature, regarding it as anartificial heat/cold source. The device can be programmed to respondeither way, i.e., sending temperature data over the network and havingit acted upon or internally filtering it out and ignoring it.

If a message is sent, the actual temperature value may or may not besent depending on the configuration setup of the device. For example, ifit is a false influence, the rapid change in temperature should beignored and not displayed on the network or a local display, e.g., LCDdisplay. To determine whether the current temperature is changing toofast, the previous temperature is compared to the current temperature.If the difference is too large per a specific time interval, then themethod continues with step 374. If not, the method continues with step364.

Next, the temperature reading just calculated is compared with theprevious reading. If the difference is greater than a threshold (step364) then the current temperature is transmitted over the network (step366). If the difference is less than or equal to the threshold, thetemperature is transmitted over the network (step 370) if the TEMP_TIMERtimer expired (step 368). The timer is then reset (step 372).

The previous temperature is set equal to the current temperature (step374) and the TEMP_SENSOR flag is cleared (step 376).

A flow diagram illustrating the set point adjustment portion of thesoftware in more detail is shown in FIG. 31. The user interacts with thetemperature set point adjustment features of the device via the up anddown buttons 43 (FIG. 1). If either set point button is pressed for morethan a predetermined time interval, e.g., 3 seconds (step 580), thecurrently configured set point is displayed (step 582). At this point,if either set point button is pressed (step 584), the current set pointis incremented or decremented depending on which set point button waspressed (step 586). If neither set point button is pressed for longerthan a predefined length of time, e.g., 10 seconds (step 588), thedisplay shows the current temperature (step 590).

A flow diagram illustrating the thermostat portion of the software inmore detail is shown in FIG. 32. This routine is run on a continuouslybasis and may be adapted to run in the LonWorks programming andoperating environment. In particular, the method may be implemented bycreating one or more events that are periodically monitored. When anoccurrence is detected, the corresponding procedure is executed.

First, the current temperature reading is compared to the currentlyconfigured set point (step 600). If the current temperature has fallenbelow or risen above a predefined range or difference, e.g., +/−1.5degrees Celsius (step 610), then cooling, heating and/or a fan is turnedon (step 612) and a hold timer is set (step 614). Note that in this stepand the steps that follow, the cooling, heating and fan can becontrolled by a variety of ways, such as the following alone or incombination: via one or more network updates, via a relay toggle whereinthe relay is integral with the device or is situated remotely on thenetwork.

If the current temperature falls within the predefined range ordifference, e.g., +/−1.5 degrees Celsius (step 610), then cooling,heating and/or a fan is turned off (step 632) and a hold timer isstopped (step 634).

Once the hold timer has expired (step 616), it is checked whether thecurrent temperature has fallen below or risen above a predefined range,e.g., +/−1.5 degree Celsius (step 618). If it has, cooling, heatingand/or a fan is turned off (step 620) and a wait timer is set (step622).

Once the wait timer expires (step 624), it is checked whether thetemperature has fallen below or risen above a predefined range (step626), e.g., +/−1.5 degrees Celsius. If it has, control continues withstep 612 and the cooling, heating and/or fan is turned on.

A flow diagram illustrating the fast change portion of the software inmore detail is shown in FIG. 33. The temperature is first calculated(step 640) and then stored as a fast change temperature value (step642). A fast change timer is then set (step 644). When the fast changetimer expires (step 646), the stored fast change temperature is comparedto the current temperature (step 648).

If the temperature difference falls below or above a predefined range(step 650), e.g., 15 degrees Celsius, then do not update the temperaturevalue and send a warning message via the network and/or set a beepingsignal at a slow interval (step 652). A fast change timer is then set(step 654).

The current temperature exceeds a predefined alert temperature, e.g., 50degrees Celsius (step 656), then send an alert message via the networkand/or set a beeping signal at a fast interval (step 658).

Humidity

The humidity task 323 is operative to periodically sense the currenthumidity level via the HUM. signal output of the humidity sensor circuit199. Depending on the desired application, the humidity reading measuredcan be displayed locally and/or transmitted to a remote location via thenetwork, such as to a central monitoring station.

Relay

The relay task 313 functions to control the on and off state of the oneor more relays connected to the unit. Each relay has an associated relaydriver circuit 490 (FIG. 24) and a relay load. Using network variableswithin the context of a LonWorks based network, the relay task mayrespond, i.e., be bound, to various network variables. The relay taskmay be suitably programmed to respond to settings of an ON/AUTO/OFFswitch on a switch or dimming device. If the switching input value isset to on, then the relay is turned on regardless of the setting of abound occupancy sensor device or other sensor device. Thus, if a userturns the switch to the ON position, the relay task would respond byturning the relay on provided that the control unit is not in theinhibited sate (described in more detail hereinbelow). The relay wouldstay on, regardless of the state of other bound sensor devices such asoccupancy sensor devices. The relay task also responds to the on/offcommands from a bound switch device, turning the relay on and offaccordingly. When in the AUTO state, the relay load is controlled by thesensors bound to it over the network.

The relay task 313 also comprises means of controlling the relay loadlocally via one or more switch integral to the device. The relay task isadapted to optionally control the relay load in response to varioussensors within the device, e.g., temperature, humidity, motion, ambientlight.

Dimming

The dimming task 326 implements the dimming functionality of the unitand functions to control a dimming load connected to a control unit orother dimming device directly or via the network. The unit 150 isconnected to the network and bound to one or more control units.Brighten and dim commands are generated by the dimming task andtransmitted onto the network. In response, the dimming task in thecorresponding control units brightens or dims its associated dimmingload accordingly.

A network may utilize a plurality of dimming sensors and a control unitcoupled to a logical dimming load. The plurality of dimming sensors isbound to the control unit via the network. The logical dimming load,represented by one or more physical dimming electrical loads, isconnected to the control unit. Note that the control unit may be adaptedto control any number of logical or physical dimming loads. In addition,a feedback signal is bound from the control unit to each of the units150. It is also the intent of the invention to allow for the dimmingelement and software to be incorporated within the sensor device 110 aswell. That is, the control unit described above was described as aseparate device for illustration purposes only, i.e., as an illustrationof how the loads can be dimmed, and does not necessarily have to beconstructed as a separate device.

On each of the units 150, the brightness level is adjusted by pressing aswitch 28 (FIG. 1), 122, 124 (FIG. 9), 123, 125 (FIG. 10). Pressing onthe switch increases the brightness level by an incremental amount,e.g., ½ or 1 full unit of resolution if the feedback equals zero. Whenthe switch is pressed, a command is sent from the unit to the controlunit that it is bound to. To dim the light, the switch is pressed againwhich causes a command to be sent to the control unit instructing it todim the load bound to it.

Note that on single switch units, the single switch performs eitheron/off control or brighten/dim control. On two-switch units, on/off andbrighten/dim control are provided for each load. Unit 110 (FIG. 10)alternatively uses two switches (an up and a down) to control singledimming load.

If the light was previously off, i.e., feedback equals zero, thenquickly tapping the switch will turn the lights on in accordance withthe Lighting Priority Order described above. Once on, a quick tap on theswitch will turn the lights off. Once on, if the switch is pressed andheld, the brightness level increases until the maximum brightness levelis reached at which point no further action occurs. As the light levelramps up, the user ceases holding the switch and the light level reachedat that point is used. Maximum brightness can be achieved faster byquickly tapping twice on the switch. Similarly, pressing and holding theswitch causes the light level to dim until the user cases holding theswitch. Continuously holding the switch causes the light to dim to thecompletely off level.

If more than one unit 150 sensor is bound to the same dimming load inthe control unit, then feedback is used to communicate information fromthe control unit to each of the units bound to it. Feedback is utilizedto inform the other units that are also controlling the dimming load asto the state of the dimming load. Thus, all the units are synchronizedand via feedback from the control unit are able to effectively track theactions of each other. The control unit preferably sends the feedbackinformation after each command is received. For example, feedback may besent to all the bound unit 200 ms after the last command related to thelight level is received.

The dimming task 326 also functions to control a dimming load that isconnected to the device itself utilizing the dimming circuitry 510, 530(FIGS. 25 and 26). The above description of the dimming functions applywith the difference that commands are not sent over the network but thelocal dimming circuits are actuated directly.

The dimming task 326 also comprises a ballast dimming capability whichfunctions similarly to the dimming function described above but isadapted to control fluorescent lights. The ballast dimming circuit 510(FIG. 25) outputs a 0 to 10 V signal that is input to an electronicballast. In response to the level of the signal, the light level of thefluorescent lamp is set accordingly. The relay and 0 to 10 V dinuningballast functions can be used together to provide approximately 0 to99.9% dimming and then a positive off by opening the relay. The lightbar underneath the user interface rocker switch or touch sensitivescreen or plate is illuminated to the appropriate level indicating therelative lighting level in the room.

Power On/Off/Auto Task

The power on/off task 328 functions to control the on and off control ofa relay in the control unit that is bound to the unit. The taskfunctions similarly to the dimming task, with the difference being thatthe load is turned off and on rather than dimmed and brightened. Similarto the case of dimming, the on/off control of a load also may includebinding a feedback variable to all the dimmer/switch units bound to aparticular load connected to the control unit.

Each relay in the control unit has an associated relay driver circuitand a relay load. Using network variables within the context of aLonWorks based network, the task may respond, i.e., be bound, to variousnetwork variables and/or other input. For example, the task may besuitably programmed to respond to settings of the ON/AUTO/OFF modeswitch 160 (FIG. 14) on the unit. If the mode is set to on, then therelay is turned on regardless of the setting of a bound occupancy sensordevice or other sensor device. Thus, if a user turns the switch to theON position, the task functions to transmit a command to the controlunit to turn the relay on (provided that the control unit is not in theinhibited sate). The relay would stay on, regardless of the state ofother bound sensor devices such as occupancy sensor devices. The taskalso responds to the on/off commands from the switch 28 (FIG. 1); 122,124 (FIG. 9), turning the relay on and off accordingly. When in the AUTOstate, the relay load is controlled by switch closures on the unit 150via variables bound to it over the network.

California Title 24

The California Title 24 task 329 functions to modify the operation ofthe power on/off and dimming tasks. This task prevents the relay ordimming load from turning on when there is sufficient light. Thus, theoccupancy sensor or switch input sensor bound to the relay or dimmingload attached to the control unit will not be able to turn therespective load on. In addition, if a sensor has already turned the loadon, a switch input can only turn them off but not back on.

In connection with the dimming task described above, if there issufficient light in the room, the lights will not turn on or brighten toa ‘turn on’ or brighten command from a unit bound to the light.

In connection with the occupancy task 320, the lights will not turn onif there is sufficient light in the room. In the California Title 24mode, the lights may only be turned on via the occupancy sensorcircuitry detecting motion. A user may, however, dim the lights and turnthem off via a switch. A user may brighten the lights but they willimmediately dim in accordance with the light harvesting setting, iflight harvesting is active. If light harvesting is not active,attempting to brighten and/or turn the lights on via a switch will haveno effect.

While the invention has been described with respect to a limited numberof embodiments, it will be appreciated that many variations,modifications and other applications of the invention may be made.

1-59 (Canceled)
 60. A multiple sensor and control device for use on alocal operating network, comprising: a communications transceiver fortransmitting and receiving data between said multiple sensor device andsaid local operating network; a plurality of sensor devices each sensordevice adapted to measure a physical phenomenon; and control means fordetermining a level of electrical power to be applied to a loadelectrically connected to said multiple sensor and control device. 61.The device according to claim 60, wherein said sensor device comprises amotion sensor.
 62. The device according to claim 60, wherein said sensordevice comprises motion sensing circuitry including a passive infrared(PIR) sensor.
 63. The device according to claim 60, wherein said sensordevice comprises an ambient light sensor.
 64. The device according toclaim 60, wherein said sensor device comprises ambient light sensingcircuitry including a photodiode.
 65. The device according to claim 60,wherein said sensor device comprises a temperature sensor.
 66. Thedevice according to claim 60, wherein said sensor device comprisestemperature sensing circuitry including said temperature sensor element.67. The device according to claim 60, wherein said sensor devicecomprises a humidity sensor.
 68. The device according to claim 60,further comprising a housing to accommodate at least one of saidcommunication transceiver, plurality of sensor devices and said controlmeans.
 69. The device according to claim 68, wherein said housingcomprises a cavity adapted to contain a temperature sensor elementwherein said cavity is substantially sealed from the rest of said devicebut open to the environment via a vent such that said temperature sensorelement is coupled to the surrounding environment but is neither exposedto the flow of air in the surrounding area nor lies in an airflowchannel within said device, the temperature of the air within saidcavity changing via diffusion with the air in the surroundingenvironment.
 70. The device according to claim 68, wherein said housingcomprises a cavity adapted to contain a temperature sensor elementwherein said cavity is substantially sealed from the rest of said devicebut open to the environment via a vent in combination with one or morechannels adapted to direct air flow in from said vent, over saidtemperature sensing element, through said channels and out one or morevent holes located on the front surface of said housing.
 71. The deviceaccording to claim 68, further comprising a pedestal within said housingwherein a temperature sensor element is positioned at a distance from aprinted circuit board, said pedestal adapted to substantiallyenvironmentally seal said cavity from an inner portion of said housing.72. The device according to claim 68, wherein said housing comprisesopenings on one side only so as to direct airflow through an area thatdoes not impact any circuitry located therewithin.
 73. The deviceaccording to claim 60, further comprising means for communicating one ormore quantities representing measured said physical phenomena over saidlocal operating network.
 74. The device according to claim 60, whereinsaid control means comprises relay control circuitry.
 75. The deviceaccording to claim 60, wherein said control means comprises ballastdimming circuitry.
 76. The device according to claim 60, wherein saidcontrol means comprises dimming circuitry.
 77. The device according toclaim 60, wherein said control means comprises at least one electricalswitch means operable by a user for turning electrical power to a loadon and off, said device operative to communicate the actions of saiduser over said local operating network.
 78. The device according toclaim 60, wherein said control means comprises at least one electricalswitch means operable by a user for brightening and dimming a logicalelectrical lighting load, said device operative to communicate theactions of said user over said communications network.
 79. The deviceaccording to claim 60, further comprising one or more movable ortranslucent blinders for adjusting the field of view or amount ofradiation falling on one or more motion detectors.
 80. The deviceaccording to claim 60, wherein said blinder comprises an elongatedshutter portion supported by a lower wall and an upper wall, saidblinder pivotally mounted via a cylindrical stud wherein said blinderpivots on an axis perpendicular to said cylindrical stud.
 81. Themultiple sensor device according to claim 60, wherein said softwareapplication task comprises relay software application code forcontrolling the power on/off state of one or more lighting loads boundto and/or physically connection to said device.
 82. The device accordingto claim 60, further comprising a controller programmed to: execute oneor more software application tasks stored in a memory means for storinginformation; receive information over said local operating network fromone or more electrical devices; and transmit information over said localoperating network to one or more electrical devices.
 83. The deviceaccording to claim 82, wherein said software application task comprisesdimming software application code for providing dimming and brighteningcontrol of one or more dimming loads bound to said device.
 84. Thedevice according to claim 82, wherein said software application taskcomprises occupancy software application code for controlling a logicallighting load bound to said device in accordance with the detection ofmotion in an area.
 85. The device according to claim 82, wherein saidsoftware application task comprises California Title 24 softwareapplication code for modifying relay and dimming functionality inaccordance therewith.
 86. The device according to claim 82, wherein saidsoftware application task comprises ambient light level softwareapplication code for maintaining a particular light level within anarea.
 87. The device according to claim 82, wherein said softwareapplication task comprises reset software application code for placingsaid device in an initialization state.
 88. The device according toclaim 82, wherein said software application task comprises gounconfigured software application code for placing said device in anunconfigured state.
 89. The device according to claim 82, wherein saidsoftware application task comprises communication input/output (I/O)software application code for receiving data from and/or transmittingdata to said local operating network.
 90. The device according to claim82, wherein said software application task comprises inhibit softwareapplication code for inhibiting and overriding the normal operating modeof said device.
 91. The device according to claim 82, wherein saidsoftware application task comprises temperature software applicationcode for measuring the temperature of the area surrounding said device.92. The device according to claim 82, wherein said software applicationtask comprises temperature software application code for providing athermostat function adapted to control temperature by controllingartificial and natural cooling, heating and/or fan means.
 93. The deviceaccording to claim 82, wherein said software application task comprisesfast change application code for detecting rapid increases intemperature and in response thereto sending a warning message over saidlocal operating network.
 94. The device according to claim 60, whereinsaid local operating network comprises twisted pair wiring.
 95. Thedevice according to claim 60, wherein said local operating networkcomprises radio frequency (RF) communications.
 96. The device accordingto claim 60, wherein said local operating network comprises infraredcommunications.
 97. The device according to claim 60, wherein said localoperating network comprises optical communication over optical fiber.98. The multiple sensor device according to claim 60, wherein said localoperating network comprises power line carrier communications.
 99. Thedevice according to claim 60, wherein said local operating networkcomprises coaxial communications.
 100. The device according to claim 60,wherein said local operating network utilizes a standard protocol suchas LonWorks, CEBus, X10, BACNet and CAN or any other proprietaryprotocol.
 101. The device according to claim 60, wherein said memorymeans comprises random access memory (RAM).
 102. The device according toclaim 60, wherein said memory means comprises read only memory (ROM).103. The device according to claim 60, wherein said memory meanscomprises electrically erasable programmable read only memory (EEPROM).104. The device according to claim 60, wherein said communicationstransceiver comprises a twisted pair wiring transceiver.
 105. The deviceaccording to claim 60, wherein said communications transceiver comprisesa radio frequency (RF) transceiver.
 106. The device according to claim60, wherein said communications transceiver comprises a power linecarrier transceiver.
 107. The device according to claim 60, wherein saidcommunications transceiver comprises an infrared (IR) transceiver. 108.The device according to claim 60, wherein said communicationstransceiver comprises an optical fiber transceiver.
 109. The deviceaccording to claim 60, wherein said communications transceiver comprisesa coaxial cable transceiver.
 110. The device according to claim 60,wherein said communications transceiver comprises an FFT-10A twistedpair wiring transceiver.
 111. The device according to claim 60, whereinsaid controller comprises a Neuron 3120 integrated circuit.
 112. Thedevice according to claim 60, wherein said controller comprises amicroprocessor, microcontroller or custom integrated circuit thatemploys the LonTalk EIA 709.1 protocol.
 113. The device according toclaim 60, wherein said load comprises one or more physical electricallighting loads.
 114. The device according to claim 60, wherein said loadcomprises one or more logical electrical lighting loads.
 115. The deviceaccording to claim 60, further comprising a press to release buttonadapted to permit the device to be removed from a wall and used as aremote control as well as a regular wall mounted or table top switch ordimmer, sensor or thermostat and adapted to control natural andartificial lighting, temperature and humidity devices.
 116. The deviceaccording to claim 60, further comprising a display adapted to display atimer readout.
 117. The device according to claim 60, further comprisinga display adapted to display the time of day.
 118. The device accordingto claim 60, further comprising a display adapted to displaytemperature.
 119. The device according to claim 60, further comprising alight bar adapted to display the illumination state of a lighting load.